diff --git a/.env.example b/.env.example
index f838443..e54e7c7 100644
--- a/.env.example
+++ b/.env.example
@@ -31,6 +31,8 @@ TALLYNOTE_INSTALL_PREFIX=./
 TALLYNOTE_UPDATE_METADATA_URL=https://git.awaioi.com/api/v1/repos/awaioi/TallyNote/releases/latest
 TALLYNOTE_UPDATE_ALLOWED_HOSTS=git.awaioi.com
 TALLYNOTE_UPDATE_MAX_MB=512
+# Per-request timeout for update metadata, checksums, signatures, and archives.
+TALLYNOTE_UPDATE_TIMEOUT_SECONDS=30
 # SHA-256 is always required. Detached Ed25519 signatures are optional; set
 # this to true only when a root-managed public key is configured below.
 TALLYNOTE_UPDATE_REQUIRE_SIGNATURE=false
diff --git a/package.json b/package.json
index 9bc31df..6e4e08b 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "tallynote",
-  "version": "1.2.3",
+  "version": "1.2.4",
   "private": true,
   "type": "module",
   "packageManager": "pnpm@9.0.6",
diff --git a/scripts/tallynote-update-runner.sh b/scripts/tallynote-update-runner.sh
index 43217a0..afb6885 100755
--- a/scripts/tallynote-update-runner.sh
+++ b/scripts/tallynote-update-runner.sh
@@ -10,6 +10,8 @@ DATA_DIR=${TALLYNOTE_DATA_DIR:-/var/lib/tallynote}
 REQUEST_FILE="$DATA_DIR/update-request.json"
 CURRENT_LINK="$PREFIX/current"
 STATE_FILE="$PREFIX/.update-state"
+LOCK_FILE="$PREFIX/.update-runner.lock"
+RUNNER_LOG="$PREFIX/.update-runner.log"
 SERVICE_NAME=${TALLYNOTE_SERVICE_NAME:-tallynote.service}
 HOST=${TALLYNOTE_HOST:-127.0.0.1}
 PORT=${TALLYNOTE_PORT:-3000}
@@ -19,13 +21,72 @@ if [[ "$HEALTH_HOST" == :: ]]; then HEALTH_HOST=::1; fi
 if [[ "$HEALTH_HOST" == *:* && "$HEALTH_HOST" != \[* ]]; then HEALTH_HOST="[$HEALTH_HOST]"; fi
 
 die() { printf 'tallynote update runner: %s\n' "$*" >&2; exit 1; }
+
+# The runner may exit during any of the checks below. Install its EXIT cleanup
+# before doing privileged preflight so a partial invocation never leaves a
+# heartbeat or lock behind.
+STATE_CREATED=0
+heartbeat_pid=''
+heartbeat_owner=$$
+RUNNER_LOCK_FD=9
+RUNNER_LOCK_MODE=''
+stop_heartbeat() {
+  if [[ -n "$heartbeat_pid" ]]; then
+    kill "$heartbeat_pid" 2>/dev/null || true
+    wait "$heartbeat_pid" 2>/dev/null || true
+    heartbeat_pid=''
+  fi
+}
+# shellcheck disable=SC2329 # invoked indirectly by the EXIT trap
+release_runner_lock() {
+  if [[ "$RUNNER_LOCK_MODE" == flock ]]; then
+    flock -u "$RUNNER_LOCK_FD" 2>/dev/null || true
+    eval "exec ${RUNNER_LOCK_FD}>&-" 2>/dev/null || true
+  elif [[ "$RUNNER_LOCK_MODE" == mkdir ]]; then
+    rmdir -- "$LOCK_FILE.d" 2>/dev/null || true
+  fi
+}
+# shellcheck disable=SC2329 # invoked indirectly by the EXIT trap
+early_cleanup() {
+  local result=$?
+  stop_heartbeat
+  if (( result != 0 )); then
+    # A preflight failure happens before the normal phase-specific trap is
+    # installed. Remove only the one-shot request marker; never remove an
+    # existing recovery marker unless this invocation created it.
+    rm -f -- "$REQUEST_FILE" 2>/dev/null || true
+    if (( STATE_CREATED == 1 )); then rm -f -- "$STATE_FILE" 2>/dev/null || true; fi
+  fi
+  release_runner_lock
+  return "$result"
+}
+trap early_cleanup EXIT
+
 [[ ${EUID:-$(id -u)} -eq 0 ]] || die 'must run as root'
+[[ -d "$PREFIX" ]] || die 'install prefix is missing'
+if command -v flock >/dev/null 2>&1; then
+  exec 9>"$LOCK_FILE" || die '无法打开更新运行锁'
+  flock -n "$RUNNER_LOCK_FD" || exit 0
+  RUNNER_LOCK_MODE=flock
+else
+  # macOS development fixtures do not ship util-linux; retain an atomic lock
+  # fallback there while Linux production uses flock above.
+  mkdir "$LOCK_FILE.d" 2>/dev/null || exit 0
+  RUNNER_LOCK_MODE='mkdir'
+fi
 [[ -f "$REQUEST_FILE" || -f "$STATE_FILE" ]] || exit 0
 [[ -L "$CURRENT_LINK" ]] || die 'current release link is missing'
 
 old_target=$(readlink -f -- "$CURRENT_LINK")
 [[ "$old_target" == "$PREFIX/releases/"* && -d "$old_target" ]] || die 'current release target is invalid'
 
+# Capture the service state before any download/apply work. The value is
+# persisted in the recovery marker so a later runner process can restore the
+# operator's original state after a crash (the service is normally inactive by
+# the time recovery starts).
+was_active=0
+if systemctl is-active --quiet "$SERVICE_NAME"; then was_active=1; fi
+
 request_operation='apply'
 if [[ -f "$REQUEST_FILE" && ! -L "$REQUEST_FILE" ]]; then
   request_operation=$(sed -n 's/.*"operation"[[:space:]]*:[[:space:]]*"\(download\|apply\)".*/\1/p' "$REQUEST_FILE" | head -n 1)
@@ -39,15 +100,11 @@ job_id=''
 if [[ -f "$REQUEST_FILE" && ! -L "$REQUEST_FILE" ]]; then
   job_id=$(sed -n 's/.*"jobId"[[:space:]]*:[[:space:]]*"\([0-9a-f-]*\)".*/\1/p' "$REQUEST_FILE" | head -n 1)
 fi
-STATE_CREATED=0
-heartbeat_pid=''
-heartbeat_owner=$$
-
 write_recovery_state() {
   local phase=$1 temporary
   temporary="$PREFIX/.update-state-$$-${RANDOM}.tmp"
   [[ ! -e "$temporary" && ! -L "$temporary" ]] || return 1
-  printf 'job_id=%s\nold_target=%s\nphase=%s\n' "$job_id" "$old_target" "$phase" > "$temporary"
+  printf 'job_id=%s\nold_target=%s\nphase=%s\ninitial_active=%s\n' "$job_id" "$old_target" "$phase" "$was_active" > "$temporary"
   chmod 600 "$temporary"
   mv -Tf -- "$temporary" "$STATE_FILE"
   STATE_CREATED=1
@@ -59,14 +116,6 @@ clear_recovery_state() {
   STATE_CREATED=0
 }
 
-stop_heartbeat() {
-  if [[ -n "$heartbeat_pid" ]]; then
-    kill "$heartbeat_pid" 2>/dev/null || true
-    wait "$heartbeat_pid" 2>/dev/null || true
-    heartbeat_pid=''
-  fi
-}
-
 heartbeat() {
   # Keep the lease fresh during long downloads/backups, but stop on a hard
   # runner kill so an orphaned child cannot keep the recovery marker alive.
@@ -86,9 +135,11 @@ start_heartbeat() {
 # This trap covers failures before the normal apply cleanup trap is installed,
 # including a missing runtime, an invalid current link, and a failed service
 # stop. It deliberately does not remove a pre-existing recovery marker.
+# shellcheck disable=SC2329 # invoked indirectly by the EXIT trap
 preflight_cleanup() {
   local result=$?
   stop_heartbeat
+  release_runner_lock
   if (( result != 0 )); then
     rm -f -- "$REQUEST_FILE" 2>/dev/null || true
     if (( STATE_CREATED == 1 )); then clear_recovery_state || true; fi
@@ -97,6 +148,33 @@ preflight_cleanup() {
 }
 trap preflight_cleanup EXIT
 
+DOWNLOAD_TIMEOUT_SECONDS=${TALLYNOTE_UPDATE_DOWNLOAD_TIMEOUT_SECONDS:-${TALLYNOTE_UPDATE_RUNNER_DOWNLOAD_TIMEOUT_SECONDS:-1800}}
+APPLY_TIMEOUT_SECONDS=${TALLYNOTE_UPDATE_APPLY_TIMEOUT_SECONDS:-${TALLYNOTE_UPDATE_RUNNER_APPLY_TIMEOUT_SECONDS:-1800}}
+FINALIZE_TIMEOUT_SECONDS=${TALLYNOTE_UPDATE_FINALIZE_TIMEOUT_SECONDS:-${TALLYNOTE_UPDATE_RUNNER_FINALIZE_TIMEOUT_SECONDS:-30}}
+TIMEOUT_BIN=$(command -v timeout || true)
+
+run_update_cli() {
+  local node=$1 timeout_seconds=$2 label=$3 result
+  shift 3
+  [[ "$timeout_seconds" =~ ^[1-9][0-9]*$ ]] || die "${label} timeout must be a positive integer"
+  {
+    printf '\n[%s] %s (timeout=%ss)\ncommand:' "$(date -u '+%Y-%m-%dT%H:%M:%SZ')" "$label" "$timeout_seconds"
+    printf ' %q' "$node" "$CURRENT_LINK/dist/server/cli/update.js" "$@"
+    printf '\n'
+  } >>"$RUNNER_LOG"
+  if [[ -n "$TIMEOUT_BIN" ]]; then
+    "$TIMEOUT_BIN" --foreground --signal=TERM --kill-after=10s "${timeout_seconds}s" \
+      "$node" "$CURRENT_LINK/dist/server/cli/update.js" "$@" >>"$RUNNER_LOG" 2>&1
+    result=$?
+  elif "$node" "$CURRENT_LINK/dist/server/cli/update.js" "$@" >>"$RUNNER_LOG" 2>&1; then
+    result=0
+  else
+    result=$?
+  fi
+  printf '[%s] %s exited with status %s\n' "$(date -u '+%Y-%m-%dT%H:%M:%SZ')" "$label" "$result" >>"$RUNNER_LOG"
+  return "$result"
+}
+
 # Downloading is intentionally handled while the main service remains up.
 # The CLI persists the validated payload under the root-owned workspace and
 # leaves the job staged for a later apply request.
@@ -107,6 +185,7 @@ if [[ "$request_operation" == download ]]; then
     clear_recovery_state || die '无法清理上一次下载状态'
   fi
   write_recovery_state download || die '无法写入更新恢复状态'
+# shellcheck disable=SC2329 # invoked indirectly by the EXIT trap
   cleanup_download() {
     local result=$?
     stop_heartbeat
@@ -116,6 +195,7 @@ if [[ "$request_operation" == download ]]; then
       rm -f -- "$REQUEST_FILE" 2>/dev/null || true
     fi
     clear_recovery_state || true
+    release_runner_lock
     return "$result"
   }
   trap cleanup_download EXIT
@@ -128,7 +208,7 @@ if [[ "$request_operation" == download ]]; then
   cli="$CURRENT_LINK/dist/server/cli/update.js"
   [[ -f "$cli" ]] || die 'update CLI not found in current release'
   set +e
-  "$node_bin" "$cli" --request-file "$REQUEST_FILE"
+  run_update_cli "$node_bin" "$DOWNLOAD_TIMEOUT_SECONDS" download --request-file "$REQUEST_FILE"
   download_result=$?
   set -e
   if (( download_result != 0 )); then
@@ -139,7 +219,7 @@ if [[ "$request_operation" == download ]]; then
     download_job_id=$(sed -n 's/.*"jobId"[[:space:]]*:[[:space:]]*"\([0-9a-f-]*\)".*/\1/p' "$REQUEST_FILE" | head -n 1)
     if [[ "$download_job_id" =~ ^[0-9a-f-]{36}$ ]]; then
       for _ in 1 2 3; do
-        if "$node_bin" "$cli" --finalize-job "$download_job_id" --finalize-status failed --message '更新下载失败' >/dev/null 2>&1; then break; fi
+        if run_update_cli "$node_bin" "$FINALIZE_TIMEOUT_SECONDS" finalize-download --finalize-job "$download_job_id" --finalize-status failed --message '更新下载失败'; then break; fi
         sleep 1
       done
     fi
@@ -150,12 +230,11 @@ if [[ "$request_operation" == download ]]; then
   exit 0
 fi
 
-was_active=0
-if systemctl is-active --quiet "$SERVICE_NAME"; then was_active=1; fi
 # shellcheck disable=SC2329 # invoked indirectly by the EXIT trap below
 restore_initial_service() {
   local result=$?
   stop_heartbeat
+  release_runner_lock
   if (( result != 0 )); then
     rm -f -- "$REQUEST_FILE" 2>/dev/null || true
     if (( STATE_CREATED == 1 )); then clear_recovery_state || true; fi
@@ -175,11 +254,11 @@ finalize_state_job() {
   local node=$1 status=$2 state_job=$3
   [[ "$state_job" =~ ^[0-9a-f-]{36}$ && -n "$node" ]] || return 1
   [[ -f "$CURRENT_LINK/dist/server/cli/update.js" ]] || return 1
-  "$node" "$CURRENT_LINK/dist/server/cli/update.js" --finalize-job "$state_job" --finalize-status "$status" --message '新版本健康检查失败，已恢复上一版本' >/dev/null 2>&1
+  run_update_cli "$node" "$FINALIZE_TIMEOUT_SECONDS" finalize-recovery --finalize-job "$state_job" --finalize-status "$status" --message '新版本健康检查失败，已恢复上一版本'
 }
 
 recover_stale_state() {
-  local state_job state_old state_phase current_target recovery_node rollback_link state_mode state_uid
+  local state_job state_old state_phase state_initial_active current_target recovery_node rollback_link state_mode state_uid
   [[ -f "$STATE_FILE" && ! -L "$STATE_FILE" ]] || die 'update state file is invalid'
   state_uid=$(stat -c '%u' "$STATE_FILE" 2>/dev/null || stat -f '%u' "$STATE_FILE")
   state_mode=$(stat -c '%a' "$STATE_FILE" 2>/dev/null || stat -f '%Lp' "$STATE_FILE")
@@ -187,8 +266,16 @@ recover_stale_state() {
   state_job=$(sed -n 's/^job_id=//p' "$STATE_FILE" | head -n 1)
   state_old=$(sed -n 's/^old_target=//p' "$STATE_FILE" | head -n 1)
   state_phase=$(sed -n 's/^phase=//p' "$STATE_FILE" | head -n 1)
+  state_initial_active=$(sed -n 's/^initial_active=//p' "$STATE_FILE" | head -n 1)
   [[ "$state_job" =~ ^[0-9a-f-]{36}$ ]] || die 'update state job id is invalid'
   [[ "$state_old" == "$PREFIX/releases/"* && -d "$state_old" && ! -L "$state_old" ]] || die 'update state target is invalid'
+  if [[ -z "$state_initial_active" ]]; then
+    # Markers from older releases did not persist this field. Preserve their
+    # historical conservative behavior instead of rejecting recovery.
+    state_initial_active=0
+  fi
+  [[ "$state_initial_active" == 0 || "$state_initial_active" == 1 ]] || die 'update state initial service state is invalid'
+  was_active=$state_initial_active
   current_target=$(readlink -f -- "$CURRENT_LINK" 2>/dev/null || true)
   if [[ "$state_phase" == download && "$current_target" == "$state_old" ]]; then
     # Downloading never changes the active release. If the runner was killed
@@ -312,7 +399,7 @@ finalize_failed_job() {
   # Give SQLite a moment to release a transient lock before declaring the
   # recovery itself failed.
   for _ in 1 2 3; do
-    if "$old_node" "$CURRENT_LINK/dist/server/cli/update.js" --finalize-job "$job_id" --finalize-status failed --message '新版本健康检查失败，已恢复上一版本' >/dev/null 2>&1; then
+    if run_update_cli "$old_node" "$FINALIZE_TIMEOUT_SECONDS" finalize-failed --finalize-job "$job_id" --finalize-status failed --message '新版本健康检查失败，已恢复上一版本'; then
       return 0
     fi
     sleep 1
@@ -323,7 +410,7 @@ finalize_failed_job() {
 finalize_completed_job() {
   [[ "$job_id" =~ ^[0-9a-f-]{36}$ ]] || return 0
   [[ -n "$final_node" ]] || return 1
-  "$final_node" "$CURRENT_LINK/dist/server/cli/update.js" --finalize-job "$job_id" --finalize-status completed >/dev/null 2>&1
+  run_update_cli "$final_node" "$FINALIZE_TIMEOUT_SECONDS" finalize-completed --finalize-job "$job_id" --finalize-status completed
 }
 
 # shellcheck disable=SC2329 # invoked indirectly by the EXIT trap below
@@ -347,6 +434,7 @@ cleanup_after_update() {
   else
     systemctl stop "$SERVICE_NAME" || true
   fi
+  release_runner_lock
   return "$result"
 }
 trap cleanup_after_update EXIT
@@ -358,7 +446,7 @@ cli="$CURRENT_LINK/dist/server/cli/update.js"
 [[ -f "$cli" ]] || die 'update CLI not found in current release'
 
 set +e
-"$node_bin" "$cli" --request-file "$REQUEST_FILE" --defer-completion
+run_update_cli "$node_bin" "$APPLY_TIMEOUT_SECONDS" apply --request-file "$REQUEST_FILE" --defer-completion
 update_result=$?
 set -e
 if (( update_result != 0 )); then
diff --git a/server/cli/update.ts b/server/cli/update.ts
index 8f221e3..ab65384 100644
--- a/server/cli/update.ts
+++ b/server/cli/update.ts
@@ -163,7 +163,10 @@ function writeJob(sqlite: Database.Database | undefined, jobId: string, values:
       requested_at=COALESCE(excluded.requested_at, update_jobs.requested_at),
       started_at=COALESCE(excluded.started_at, update_jobs.started_at),
       operation=excluded.operation,
-      status=CASE WHEN update_jobs.status='cancelled' THEN update_jobs.status ELSE excluded.status END,
+      -- Terminal rows are immutable from the runner's ordinary progress
+      -- writes. In particular, a stale/replayed request must not resurrect a
+      -- failed job as queued/downloading/etc.
+      status=CASE WHEN update_jobs.status IN ('cancelled', 'failed', 'completed') THEN update_jobs.status ELSE excluded.status END,
       version=excluded.version, platform=excluded.platform,
       release_url=COALESCE(excluded.release_url, update_jobs.release_url),
       asset_name=COALESCE(excluded.asset_name, update_jobs.asset_name),
@@ -176,6 +179,11 @@ function writeJob(sqlite: Database.Database | undefined, jobId: string, values:
       error_message=COALESCE(excluded.error_message, update_jobs.error_message),
       updated_at=excluded.updated_at,
       completed_at=COALESCE(excluded.completed_at, update_jobs.completed_at)
+    -- Do not let a delayed runner replay overwrite any field on a terminal
+    -- row. The predicate is part of the same SQLite upsert, so a finalizer
+    -- racing this write still wins atomically instead of leaving a partially
+    -- mutated completed/failed/cancelled record.
+    WHERE update_jobs.status NOT IN ('cancelled', 'failed', 'completed')
   `).run(
     jobId,
     values.adminId ?? null,
@@ -230,6 +238,7 @@ async function resolveRelease(options: UpdateRunOptions, platform: ReturnType<ty
       allowedHosts: options.allowedHosts ?? [],
       baseUrl: metadataUrl.toString(),
       maxBytes: options.maxBytes ?? 512 * 1024 * 1024,
+      timeoutMs: options.timeoutMs,
       publicKey: options.publicKey,
       requireSignature: options.requireSignature,
     });
@@ -398,19 +407,28 @@ export function finalizeUpdateJob(
   status: "completed" | "failed",
   message?: string,
 ): void {
-  const row = sqlite.prepare(`
-    SELECT id, status, version, platform, admin_id AS adminId,
-      request_id AS requestId, session_hash AS sessionHash
-    FROM update_jobs WHERE id=?
-  `).get(jobId) as { id: string; status: UpdateJobStatus; version: string; platform: string; adminId: string | null; requestId: string | null; sessionHash: string | null } | undefined;
-  if (!row) throw new Error("更新任务不存在");
-  const canComplete = row.status === "applying" || row.status === "completed";
-  const canFail = ACTIVE_UPDATE_STATUSES.includes(row.status) || row.status === "completed" || row.status === "failed";
-  if (status === "completed" ? !canComplete : !canFail) throw new Error("更新任务状态不允许完成");
-  const now = Date.now();
-  const safeFailureMessage = status === "failed" ? "新版本健康检查失败，已恢复上一版本" : null;
   sqlite.transaction(() => {
-    sqlite.prepare("UPDATE update_jobs SET status=?, error_message=?, completed_at=?, updated_at=? WHERE id=?").run(status, safeFailureMessage, now, now, jobId);
+    const row = sqlite.prepare(`
+      SELECT id, status, version, platform, admin_id AS adminId,
+        request_id AS requestId, session_hash AS sessionHash
+      FROM update_jobs WHERE id=?
+    `).get(jobId) as { id: string; status: UpdateJobStatus; version: string; platform: string; adminId: string | null; requestId: string | null; sessionHash: string | null } | undefined;
+    if (!row) throw new Error("更新任务不存在");
+    // A failed finalization can be retried by the runner. Once it has been
+    // committed, make retries a no-op so the error and audit trail stay stable.
+    if (row.status === status) return;
+    // A completed release is terminal. A delayed recovery process must never
+    // be able to downgrade it to failed after the service was healthy.
+    if (row.status === "completed" && status === "failed") throw new Error("更新任务状态不允许完成");
+    const canComplete = row.status === "applying" || row.status === "completed";
+    const canFail = ACTIVE_UPDATE_STATUSES.includes(row.status) || row.status === "completed" || row.status === "failed";
+    if (status === "completed" ? !canComplete : !canFail) throw new Error("更新任务状态不允许完成");
+    const now = Date.now();
+    const safeFailureMessage = status === "failed"
+      ? (message?.trim() ? safeErrorMessage(new Error(message)) : "新版本健康检查失败，已恢复上一版本")
+      : null;
+    const result = sqlite.prepare("UPDATE update_jobs SET status=?, error_message=?, completed_at=?, updated_at=? WHERE id=? AND status=?").run(status, safeFailureMessage, now, now, jobId, row.status);
+    if (result.changes !== 1) return;
     writeAudit(sqlite, {
       requestId: row.requestId || randomUUID(),
       actorAdminId: row.adminId,
@@ -569,6 +587,7 @@ export async function main(config: AppConfig = loadConfig()): Promise<void> {
       ...(dataBackupArchive ? { dataBackupArchivePath: dataBackupArchive, dataBackupSource: config.dataDir } : {}),
       ...((arg("--backup-dir")) ? { backupDir: arg("--backup-dir") } : {}),
       allowedHosts: allowedHosts.length ? allowedHosts : config.updateAllowedHosts,
+      timeoutMs: config.updateTimeoutMs,
       maxBytes: config.updateMaxBytes,
       dataBackupMaxBytes: config.maxTotalBytes,
       currentVersion: config.appVersion,
diff --git a/server/config.ts b/server/config.ts
index 4440cb9..0addafc 100644
--- a/server/config.ts
+++ b/server/config.ts
@@ -147,6 +147,7 @@ export function loadConfig() {
     // as 0700 root:root; development/test callers may override --staging-dir.
     updateWorkspaceDir: path.join(installPrefix, ".update-work"),
     updateMaxBytes: integerEnv("TALLYNOTE_UPDATE_MAX_MB", 512) * 1024 * 1024,
+    updateTimeoutMs: integerEnv("TALLYNOTE_UPDATE_TIMEOUT_SECONDS", 30) * 1000,
     // Update checks hit an external release endpoint. Keep a short local
     // cooldown so an authenticated account cannot turn the endpoint into an
     // outbound request flood; set to 0 only for controlled test environments.
diff --git a/server/update-service.ts b/server/update-service.ts
index 39fe253..1f692e8 100644
--- a/server/update-service.ts
+++ b/server/update-service.ts
@@ -154,19 +154,19 @@ function signatureAssetFor(metadata: ReleaseMetadata, sums: ReleaseAsset): Relea
 export async function attachSidecarHash(
   metadata: ReleaseMetadata,
   asset: ReleaseAsset,
-  options: { allowedHosts: readonly string[]; baseUrl: string; maxBytes: number; publicKey?: string | undefined; requireSignature?: boolean | undefined },
+  options: { allowedHosts: readonly string[]; baseUrl: string; maxBytes: number; timeoutMs?: number | undefined; publicKey?: string | undefined; requireSignature?: boolean | undefined },
 ): Promise<{ asset: ReleaseAsset; signatureVerified: boolean }> {
   let signatureVerified = false;
   if (asset.sha256 && (!options.publicKey || !options.requireSignature)) return { asset, signatureVerified };
   const sums = metadata.assets.find((candidate) => /^(?:sha256sums?|checksums?)(?:\.txt)?$/i.test(path.basename(candidate.name)));
   if (!sums) return { asset, signatureVerified };
   try {
-    const content = await fetchReleaseText(sums.url, { allowedHosts: options.allowedHosts, baseUrl: options.baseUrl, maxBytes: Math.min(options.maxBytes, 2 * 1024 * 1024) });
+    const content = await fetchReleaseText(sums.url, { allowedHosts: options.allowedHosts, baseUrl: options.baseUrl, maxBytes: Math.min(options.maxBytes, 2 * 1024 * 1024), timeoutMs: options.timeoutMs });
     const sha256 = sha256FromSums(content, asset.name);
     if (options.publicKey) {
       const signatureAsset = signatureAssetFor(metadata, sums);
       if (signatureAsset) {
-        const signature = await fetchReleaseBytes(signatureAsset.url, { allowedHosts: options.allowedHosts, baseUrl: options.baseUrl, maxBytes: 64 * 1024 });
+        const signature = await fetchReleaseBytes(signatureAsset.url, { allowedHosts: options.allowedHosts, baseUrl: options.baseUrl, maxBytes: 64 * 1024, timeoutMs: options.timeoutMs });
         signatureVerified = verifyReleaseSignature(content, signature, options.publicKey);
       }
     }
@@ -183,6 +183,7 @@ function policy(config: AppConfig) {
     allowedHosts: config.updateAllowedHosts,
     baseUrl: config.updateMetadataUrl,
     maxRedirects: 3,
+    timeoutMs: config.updateTimeoutMs,
   } as const;
 }
 
@@ -222,6 +223,7 @@ export async function checkForUpdate(database: Database.Database, config: AppCon
       allowedHosts: config.updateAllowedHosts,
       baseUrl: metadataUrl,
       maxBytes: config.updateMaxBytes,
+      timeoutMs: config.updateTimeoutMs,
       publicKey: config.updatePublicKey,
       requireSignature: config.updateRequireSignature,
     });
@@ -426,6 +428,17 @@ function requestJobId(filePath: string): string | null {
   }
 }
 
+function recoveryStateJobId(filePath: string): string | null {
+  try {
+    const info = lstatSync(filePath);
+    if (!info.isFile() || info.isSymbolicLink()) return null;
+    const match = /^job_id=([0-9a-f-]{36})$/m.exec(readFileSync(filePath, "utf8"));
+    return match?.[1] ?? null;
+  } catch {
+    return null;
+  }
+}
+
 function currentReleaseVersion(config: AppConfig): string | null {
   try {
     const target = realpathSync(config.currentLink);
@@ -460,6 +473,12 @@ export function reconcileOrphanedUpdateJobs(database: Database.Database, config:
   const statePresent = stateMtime !== null;
   const requestFresh = requestPresent && now - (requestMtime ?? 0) < ORPHANED_UPDATE_TIMEOUT_MS;
   const stateFresh = statePresent && now - (stateMtime ?? 0) < ORPHANED_UPDATE_TIMEOUT_MS;
+  // The request marker is the hand-off contract between the web process and
+  // the privileged runner. A queued row with a matching, unexpired marker is
+  // still owned by that hand-off even when the runner has not written its
+  // recovery state yet (for example while systemd is starting it).
+  const requestMarkerJobId = requestPresent ? requestJobId(config.updateRequestPath) : null;
+  const stateMarkerJobId = statePresent ? recoveryStateJobId(statePath) : null;
   // A staged download is normally kept for an explicit apply. The one
   // exception is the hand-off window where the API has already changed the
   // operation to `apply` but crashed before writing the request file. That
@@ -472,7 +491,10 @@ export function reconcileOrphanedUpdateJobs(database: Database.Database, config:
     // the UI as an endless "queued" task. Once the short hand-off window has
     // elapsed and no recovery marker exists, release the queue explicitly;
     // a fresh state marker proves that the runner has already claimed it.
-    if (row.status === "queued" && typeof row.updatedAt === "number" && !stateFresh && now - row.updatedAt >= QUEUED_UPDATE_TIMEOUT_MS) {
+    const matchingFreshRequest = requestMarkerJobId === row.id && requestFresh;
+    const matchingFreshState = stateMarkerJobId === row.id && stateFresh;
+    if (row.status === "queued" && typeof row.updatedAt === "number" && !matchingFreshState && now - row.updatedAt >= QUEUED_UPDATE_TIMEOUT_MS) {
+      if (matchingFreshRequest) continue;
       const changed = database.transaction(() => {
         const result = database.prepare(`
           UPDATE update_jobs
@@ -503,7 +525,7 @@ export function reconcileOrphanedUpdateJobs(database: Database.Database, config:
     // A stale request/state marker therefore no longer protects an orphaned
     // row forever, while a fresh marker remains owned by the runner.
     if (row.status === "staged") {
-      if (row.operation !== "apply" || requestFresh || stateFresh) continue;
+      if (row.operation !== "apply" || matchingFreshRequest || matchingFreshState) continue;
       const changed = database.transaction(() => {
         const result = database.prepare(`
           UPDATE update_jobs
@@ -529,7 +551,7 @@ export function reconcileOrphanedUpdateJobs(database: Database.Database, config:
       }
       continue;
     }
-    if (requestFresh || stateFresh) continue;
+    if (matchingFreshRequest || matchingFreshState) continue;
     const status: "completed" | "failed" = row.status === "applying" && releaseVersion === row.version ? "completed" : "failed";
     const errorMessage = status === "failed" ? "更新任务超时，已释放更新队列" : null;
     const changed = database.transaction(() => {
@@ -586,15 +608,15 @@ export function cancelUpdateJob(
   jobId?: string,
 ): { cancelled: boolean; message?: string } {
   const job = jobId
-    ? database.prepare("SELECT id, status, operation, version, admin_id AS adminId, download_path AS downloadPath FROM update_jobs WHERE id=?").get(jobId) as { id: string; status: UpdateJobStatus; operation: string; version: string; adminId: string | null; downloadPath: string | null } | undefined
-    : database.prepare("SELECT id, status, operation, version, admin_id AS adminId, download_path AS downloadPath FROM update_jobs WHERE status IN ('queued', 'downloading') ORDER BY created_at DESC LIMIT 1").get() as { id: string; status: UpdateJobStatus; operation: string; version: string; adminId: string | null; downloadPath: string | null } | undefined;
+    ? database.prepare("SELECT id, status, operation, version, admin_id AS adminId, download_path AS downloadPath FROM update_jobs WHERE id=? AND admin_id=?").get(jobId, adminId) as { id: string; status: UpdateJobStatus; operation: string; version: string; adminId: string | null; downloadPath: string | null } | undefined
+    : database.prepare("SELECT id, status, operation, version, admin_id AS adminId, download_path AS downloadPath FROM update_jobs WHERE admin_id=? AND status IN ('queued', 'downloading') ORDER BY created_at DESC LIMIT 1").get(adminId) as { id: string; status: UpdateJobStatus; operation: string; version: string; adminId: string | null; downloadPath: string | null } | undefined;
 
   if (!job) return { cancelled: false, message: "当前没有处于等待调度或下载中的更新任务" };
   if (job.status !== "queued" && job.status !== "downloading") return { cancelled: false, message: "任务已进入就绪或切换阶段，无法取消" };
 
   const now = Date.now();
   const changed = database.transaction(() => {
-    const result = database.prepare("UPDATE update_jobs SET status='cancelled', error_message='已手动取消更新', completed_at=?, updated_at=? WHERE id=? AND status IN ('queued', 'downloading')").run(now, now, job.id);
+    const result = database.prepare("UPDATE update_jobs SET status='cancelled', error_message='已手动取消更新', completed_at=?, updated_at=? WHERE id=? AND admin_id=? AND status IN ('queued', 'downloading')").run(now, now, job.id, adminId);
     if (result.changes !== 1) return false;
     writeAudit(database, {
       requestId,
@@ -610,7 +632,9 @@ export function cancelUpdateJob(
   })();
 
   if (changed) {
-    forceRemoveRequest(config.updateRequestPath);
+    // The request marker is shared by the privileged runner. Never remove a
+    // newer/different administrator's request while cancelling this row.
+    if (requestJobId(config.updateRequestPath) === job.id) forceRemoveRequest(config.updateRequestPath);
     if (job.downloadPath) {
       const target = path.isAbsolute(job.downloadPath) ? job.downloadPath : path.join(config.stagingDir, job.downloadPath);
       import("node:fs/promises").then(({ rm }) => rm(target, { recursive: true, force: true })).catch(() => {});
diff --git a/server/update.ts b/server/update.ts
index 16b7d70..a6e07d6 100644
--- a/server/update.ts
+++ b/server/update.ts
@@ -59,8 +59,22 @@ export type UrlPolicy = {
   /** When allowedHosts is omitted, requests are constrained to this URL's host. */
   baseUrl?: string | URL | undefined;
   maxRedirects?: number | undefined;
+  /** Maximum time allowed for one metadata/sidecar/archive request. */
+  timeoutMs?: number | undefined;
 };
 
+/** Release an unread response body before following a redirect or returning
+ * an error. Undici keeps the underlying connection associated with a body
+ * until it is consumed or cancelled; leaving it open can exhaust sockets when
+ * an update feed repeatedly returns errors or oversized responses. */
+async function cancelResponseBody(response: Response): Promise<void> {
+  try {
+    await response.body?.cancel();
+  } catch {
+    // The body may already be consumed/closed. Cancellation is best effort.
+  }
+}
+
 function invalidVersion(): never {
   throw new Error("更新版本号无效");
 }
@@ -157,8 +171,37 @@ function metadataError(): Error {
 }
 
 const DEFAULT_METADATA_MAX_BYTES = 2 * 1024 * 1024;
+/** Maximum time allowed for one update HTTP request, including its body. */
+export const DEFAULT_UPDATE_TIMEOUT_MS = 30_000;
 export const RELEASE_NOTES_MAX_BYTES = 64 * 1024;
 
+type UpdateFetchOptions = {
+  fetchImpl?: typeof fetch | undefined;
+  maxBytes?: number | undefined;
+  timeoutMs?: number | undefined;
+};
+
+function updateTimeoutMs(options: UpdateFetchOptions): number {
+  if (options.timeoutMs !== undefined) {
+    if (!Number.isSafeInteger(options.timeoutMs) || options.timeoutMs <= 0) throw new Error("更新请求超时配置无效");
+    return options.timeoutMs;
+  }
+  const configuredSeconds = process.env.TALLYNOTE_UPDATE_TIMEOUT_SECONDS;
+  if (configuredSeconds !== undefined && configuredSeconds.trim() !== "") {
+    const seconds = Number(configuredSeconds);
+    if (!Number.isSafeInteger(seconds) || seconds <= 0) throw new Error("TALLYNOTE_UPDATE_TIMEOUT_SECONDS 必须是大于 0 的整数");
+    return seconds * 1000;
+  }
+  return DEFAULT_UPDATE_TIMEOUT_MS;
+}
+
+function beginUpdateRequest(options: UpdateFetchOptions): { signal: AbortSignal; clear: () => void } {
+  const controller = new AbortController();
+  const timer = setTimeout(() => controller.abort(), updateTimeoutMs(options));
+  timer.unref?.();
+  return { signal: controller.signal, clear: () => clearTimeout(timer) };
+}
+
 function releaseNotesText(value: unknown): string | undefined {
   if (typeof value !== "string" || value.length === 0) return undefined;
   // Gitea exposes both Markdown (body/body_html) and releaseNotes depending on
@@ -210,20 +253,29 @@ function releaseResourceUrl(value: string, current: URL, options: UrlPolicy): st
 }
 
 /** Read a fetch body without ever buffering more than the caller's bound. */
-async function readBoundedResponse(response: Response, maxBytes: number, tooLargeMessage: string): Promise<Buffer> {
+async function readBoundedResponse(response: Response, maxBytes: number, tooLargeMessage: string, signal?: AbortSignal): Promise<Buffer> {
   if (!Number.isSafeInteger(maxBytes) || maxBytes <= 0) throw new Error("响应大小限制无效");
   const contentLength = response.headers.get("content-length");
   if (contentLength !== null) {
     const declared = Number(contentLength);
-    if (Number.isFinite(declared) && declared > maxBytes) throw new Error(tooLargeMessage);
+    if (Number.isFinite(declared) && declared > maxBytes) {
+      await cancelResponseBody(response);
+      throw new Error(tooLargeMessage);
+    }
   }
   if (!response.body) return Buffer.alloc(0);
   const reader = response.body.getReader();
   const chunks: Buffer[] = [];
   let total = 0;
+  let onAbort: (() => void) | undefined;
+  const abort = signal ? new Promise<never>((_, reject) => {
+    onAbort = () => reject(new Error("更新请求超时"));
+    if (signal.aborted) onAbort();
+    else signal.addEventListener("abort", onAbort, { once: true });
+  }) : undefined;
   try {
     for (;;) {
-      const result = await reader.read();
+      const result = await (abort ? Promise.race([reader.read(), abort]) : reader.read());
       if (result.done) break;
       const chunk = Buffer.from(result.value);
       if (chunk.length > maxBytes - total) {
@@ -233,7 +285,11 @@ async function readBoundedResponse(response: Response, maxBytes: number, tooLarg
       total += chunk.length;
       chunks.push(chunk);
     }
+  } catch (error) {
+    await reader.cancel().catch(() => undefined);
+    throw error;
   } finally {
+    if (signal && onAbort) signal.removeEventListener("abort", onAbort);
     reader.releaseLock();
   }
   return Buffer.concat(chunks, total);
@@ -241,84 +297,78 @@ async function readBoundedResponse(response: Response, maxBytes: number, tooLarg
 
 export async function fetchReleaseMetadata(
   metadataUrl: string | URL,
-  options: UrlPolicy & { fetchImpl?: typeof fetch | undefined; maxBytes?: number | undefined } = {},
+  options: UrlPolicy & UpdateFetchOptions = {},
 ): Promise<ReleaseMetadata> {
   const fetchImpl = options.fetchImpl ?? fetch;
   let current = validateHttpsUrl(metadataUrl, options);
   const maxRedirects = options.maxRedirects ?? 3;
   let response: Response;
   for (let redirects = 0; ; redirects += 1) {
+    const request = beginUpdateRequest(options);
     try {
-      response = await fetchImpl(current, { method: "GET", redirect: "manual", headers: { accept: "application/json" } });
+      response = await fetchImpl(current, { method: "GET", redirect: "manual", headers: { accept: "application/json" }, signal: request.signal });
     } catch {
+      request.clear();
       throw metadataError();
     }
-    if (response.status < 300 || response.status >= 400) break;
+    if (response.status < 300 || response.status >= 400) {
+      try {
+        if (response.status < 200 || response.status >= 300) {
+          await cancelResponseBody(response);
+          throw metadataError();
+        }
+        const maxBytes = Math.min(options.maxBytes ?? DEFAULT_METADATA_MAX_BYTES, DEFAULT_METADATA_MAX_BYTES);
+        const body = await readBoundedResponse(response, maxBytes, "更新发布信息过大", request.signal);
+        const payload: unknown = JSON.parse(body.toString("utf8"));
+        if (!payload || typeof payload !== "object") throw metadataError();
+        const item = payload as Record<string, unknown>;
+        const rawVersion = typeof item.version === "string" ? item.version : typeof item.tag_name === "string" ? item.tag_name : typeof item.tagName === "string" ? item.tagName : undefined;
+        if (!rawVersion) throw metadataError();
+        const version = parseSemver(rawVersion);
+        if (typeof item.tag_name === "string" && compareSemver(version, item.tag_name) !== 0) throw metadataError();
+        const assetsRaw = Array.isArray(item.assets) ? item.assets : [];
+        const assets: ReleaseAsset[] = [];
+        for (const raw of assetsRaw) {
+          if (!raw || typeof raw !== "object") continue;
+          const asset = raw as Record<string, unknown>;
+          const name = typeof asset.name === "string" ? asset.name : undefined;
+          const url = typeof asset.url === "string" ? asset.url : typeof asset.browser_download_url === "string" ? asset.browser_download_url : undefined;
+          if (!name || !url) continue;
+          let sha256: string | undefined;
+          const digest = typeof asset.sha256 === "string" ? asset.sha256 : typeof asset.digest === "string" ? asset.digest : undefined;
+          if (digest) {
+            const candidate = digest.replace(/^sha256:/i, "").toLowerCase();
+            if (/^[a-f0-9]{64}$/.test(candidate)) sha256 = candidate;
+          }
+          assets.push({ name, url: releaseResourceUrl(url, current, options), ...(sha256 ? { sha256 } : {}), ...(typeof asset.size === "number" && Number.isSafeInteger(asset.size) && asset.size >= 0 ? { size: asset.size } : {}) });
+        }
+        const notes = releaseNotesText(item.body ?? item.releaseNotes ?? item.release_notes ?? item.body_html);
+        const releaseName = releaseNameText(item.name ?? item.releaseName);
+        let releaseUrl: string | undefined;
+        if (typeof item.html_url === "string" || typeof item.url === "string") {
+          try { releaseUrl = releaseResourceUrl(typeof item.html_url === "string" ? item.html_url : item.url as string, current, options); } catch { /* optional */ }
+        }
+        return {
+          version: `${version.major}.${version.minor}.${version.patch}${version.prerelease.length ? `-${version.prerelease.join(".")}` : ""}${version.build.length ? `+${version.build.join(".")}` : ""}`,
+          ...(typeof item.tag_name === "string" ? { tagName: item.tag_name } : {}), ...(releaseName ? { releaseName } : {}), ...(typeof item.published_at === "string" ? { publishedAt: item.published_at } : {}), ...(notes ? { notes } : {}), ...(releaseUrl ? { releaseUrl } : {}), assets,
+        };
+      } catch { throw metadataError(); }
+      finally { request.clear(); }
+    }
+    await cancelResponseBody(response);
+    request.clear();
     if (redirects >= maxRedirects) throw metadataError();
     const location = response.headers.get("location");
     if (!location) throw metadataError();
     current = validateHttpsUrl(new URL(location, current), options.baseUrl ? options : { ...options, baseUrl: current });
   }
-  if (response.status < 200 || response.status >= 300) throw metadataError();
-  let payload: unknown;
-  try {
-    const maxBytes = Math.min(options.maxBytes ?? DEFAULT_METADATA_MAX_BYTES, DEFAULT_METADATA_MAX_BYTES);
-    const body = await readBoundedResponse(response, maxBytes, "更新发布信息过大");
-    payload = JSON.parse(body.toString("utf8"));
-  } catch { throw metadataError(); }
-  if (!payload || typeof payload !== "object") throw metadataError();
-  const item = payload as Record<string, unknown>;
-  const rawVersion = typeof item.version === "string" ? item.version : typeof item.tag_name === "string" ? item.tag_name : typeof item.tagName === "string" ? item.tagName : undefined;
-  if (!rawVersion) throw metadataError();
-  const version = parseSemver(rawVersion);
-  if (typeof item.tag_name === "string") {
-    try {
-      if (compareSemver(version, item.tag_name) !== 0) throw metadataError();
-    } catch {
-      throw metadataError();
-    }
-  }
-  const assetsRaw = Array.isArray(item.assets) ? item.assets : [];
-  const assets: ReleaseAsset[] = [];
-  for (const raw of assetsRaw) {
-    if (!raw || typeof raw !== "object") continue;
-    const asset = raw as Record<string, unknown>;
-    const name = typeof asset.name === "string" ? asset.name : undefined;
-    const url = typeof asset.url === "string" ? asset.url : typeof asset.browser_download_url === "string" ? asset.browser_download_url : undefined;
-    if (!name || !url) continue;
-    let sha256: string | undefined;
-    const digest = typeof asset.sha256 === "string" ? asset.sha256 : typeof asset.digest === "string" ? asset.digest : undefined;
-    if (digest) {
-      const candidate = digest.replace(/^sha256:/i, "").toLowerCase();
-      if (/^[a-f0-9]{64}$/.test(candidate)) sha256 = candidate;
-    }
-    assets.push({ name, url: releaseResourceUrl(url, current, options), ...(sha256 ? { sha256 } : {}), ...(typeof asset.size === "number" && Number.isSafeInteger(asset.size) && asset.size >= 0 ? { size: asset.size } : {}) });
-  }
-  const notes = releaseNotesText(item.body ?? item.releaseNotes ?? item.release_notes ?? item.body_html);
-  const releaseName = releaseNameText(item.name ?? item.releaseName);
-  let releaseUrl: string | undefined;
-  if (typeof item.html_url === "string" || typeof item.url === "string") {
-    try {
-      const candidate = typeof item.html_url === "string" ? item.html_url : item.url as string;
-      releaseUrl = releaseResourceUrl(candidate, current, options);
-    } catch { /* omit invalid optional release page URL */ }
-  }
-  return {
-    version: `${version.major}.${version.minor}.${version.patch}${version.prerelease.length ? `-${version.prerelease.join(".")}` : ""}${version.build.length ? `+${version.build.join(".")}` : ""}`,
-    ...(typeof item.tag_name === "string" ? { tagName: item.tag_name } : {}),
-    ...(releaseName ? { releaseName } : {}),
-    ...(typeof item.published_at === "string" ? { publishedAt: item.published_at } : {}),
-    ...(notes ? { notes } : {}),
-    ...(releaseUrl ? { releaseUrl } : {}),
-    assets,
-  };
 }
 
 /** Fetch a small text sidecar (for example SHA256SUMS) with the same
  * redirect, HTTPS and host policy used for release metadata. */
 export async function fetchReleaseText(
   textUrl: string | URL,
-  options: UrlPolicy & { fetchImpl?: typeof fetch | undefined; maxBytes?: number | undefined } = {},
+  options: UrlPolicy & UpdateFetchOptions = {},
 ): Promise<string> {
   const fetchImpl = options.fetchImpl ?? fetch;
   let current = validateHttpsUrl(textUrl, options);
@@ -328,27 +378,32 @@ export async function fetchReleaseText(
   const maxRedirects = options.maxRedirects ?? 3;
   let response: Response;
   for (let redirects = 0; ; redirects += 1) {
+    const request = beginUpdateRequest(options);
     try {
-      response = await fetchImpl(current, { method: "GET", redirect: "manual" });
+      response = await fetchImpl(current, { method: "GET", redirect: "manual", signal: request.signal });
     } catch {
+      request.clear();
       throw new Error("更新校验文件下载失败");
     }
-    if (response.status < 300 || response.status >= 400) break;
+    if (response.status < 300 || response.status >= 400) {
+      if (response.status < 200 || response.status >= 300) { await cancelResponseBody(response); request.clear(); throw new Error("更新校验文件下载失败"); }
+      const declared = Number(response.headers.get("content-length") ?? 0);
+      const maxBytes = options.maxBytes ?? 1024 * 1024;
+      if (declared > maxBytes) { await cancelResponseBody(response); request.clear(); throw new Error("更新校验文件过大"); }
+      try {
+        return (await readBoundedResponse(response, maxBytes, "更新校验文件过大", request.signal)).toString("utf8");
+      } catch (error) {
+        if (error instanceof Error && error.message === "更新校验文件过大") throw error;
+        throw new Error("更新校验文件下载失败");
+      } finally { request.clear(); }
+    }
+    await cancelResponseBody(response);
+    request.clear();
     if (redirects >= maxRedirects) throw new Error("更新校验文件下载失败");
     const location = response.headers.get("location");
     if (!location) throw new Error("更新校验文件下载失败");
     current = validateHttpsUrl(new URL(location, current), redirectPolicy);
   }
-  if (response.status < 200 || response.status >= 300) throw new Error("更新校验文件下载失败");
-  const declared = Number(response.headers.get("content-length") ?? 0);
-  const maxBytes = options.maxBytes ?? 1024 * 1024;
-  if (declared > maxBytes) throw new Error("更新校验文件过大");
-  try {
-    return (await readBoundedResponse(response, maxBytes, "更新校验文件过大")).toString("utf8");
-  } catch (error) {
-    if (error instanceof Error && error.message === "更新校验文件过大") throw error;
-    throw new Error("更新校验文件下载失败");
-  }
 }
 
 /** Fetch a bounded binary sidecar (for example an Ed25519 detached
@@ -356,7 +411,7 @@ export async function fetchReleaseText(
  * this separate from fetchReleaseText. */
 export async function fetchReleaseBytes(
   bytesUrl: string | URL,
-  options: UrlPolicy & { fetchImpl?: typeof fetch | undefined; maxBytes?: number | undefined } = {},
+  options: UrlPolicy & UpdateFetchOptions = {},
 ): Promise<Buffer> {
   const fetchImpl = options.fetchImpl ?? fetch;
   let current = validateHttpsUrl(bytesUrl, options);
@@ -366,27 +421,32 @@ export async function fetchReleaseBytes(
   const maxRedirects = options.maxRedirects ?? 3;
   let response: Response;
   for (let redirects = 0; ; redirects += 1) {
+    const request = beginUpdateRequest(options);
     try {
-      response = await fetchImpl(current, { method: "GET", redirect: "manual" });
+      response = await fetchImpl(current, { method: "GET", redirect: "manual", signal: request.signal });
     } catch {
+      request.clear();
       throw new Error("更新签名下载失败");
     }
-    if (response.status < 300 || response.status >= 400) break;
+    if (response.status < 300 || response.status >= 400) {
+      if (response.status < 200 || response.status >= 300) { await cancelResponseBody(response); request.clear(); throw new Error("更新签名下载失败"); }
+      const declared = Number(response.headers.get("content-length") ?? 0);
+      const maxBytes = options.maxBytes ?? 64 * 1024;
+      if (declared > maxBytes) { await cancelResponseBody(response); request.clear(); throw new Error("更新签名文件过大"); }
+      try {
+        return await readBoundedResponse(response, maxBytes, "更新签名文件过大", request.signal);
+      } catch (error) {
+        if (error instanceof Error && error.message === "更新签名文件过大") throw error;
+        throw new Error("更新签名下载失败");
+      } finally { request.clear(); }
+    }
+    await cancelResponseBody(response);
+    request.clear();
     if (redirects >= maxRedirects) throw new Error("更新签名下载失败");
     const location = response.headers.get("location");
     if (!location) throw new Error("更新签名下载失败");
     current = validateHttpsUrl(new URL(location, current), redirectPolicy);
   }
-  if (response.status < 200 || response.status >= 300) throw new Error("更新签名下载失败");
-  const declared = Number(response.headers.get("content-length") ?? 0);
-  const maxBytes = options.maxBytes ?? 64 * 1024;
-  if (declared > maxBytes) throw new Error("更新签名文件过大");
-  try {
-    return await readBoundedResponse(response, maxBytes, "更新签名文件过大");
-  } catch (error) {
-    if (error instanceof Error && error.message === "更新签名文件过大") throw error;
-    throw new Error("更新签名下载失败");
-  }
 }
 
 export function selectReleaseAsset(release: ReleaseMetadata, platform = detectPlatform(), runtimeHash?: string): ReleaseAsset | undefined {
@@ -438,7 +498,7 @@ export async function verifySha256(filePath: string, expected: string): Promise<
 export async function downloadReleaseAsset(
   url: string | URL,
   destination: string,
-  options: UrlPolicy & { fetchImpl?: typeof fetch | undefined; maxBytes?: number | undefined; onProgress?: ((downloadedBytes: number, totalBytes: number | null) => void) | undefined } = {},
+  options: UrlPolicy & UpdateFetchOptions & { onProgress?: ((downloadedBytes: number, totalBytes: number | null) => void) | undefined } = {},
 ): Promise<{ size: number; sha256: string }> {
   const fetchImpl = options.fetchImpl ?? fetch;
   let current = validateHttpsUrl(url, options);
@@ -448,22 +508,32 @@ export async function downloadReleaseAsset(
   const maxRedirects = options.maxRedirects ?? 3;
   let response: Response;
   for (let redirects = 0; ; redirects += 1) {
+    const request = beginUpdateRequest(options);
     try {
-      response = await fetchImpl(current, { method: "GET", redirect: "manual" });
+      response = await fetchImpl(current, { method: "GET", redirect: "manual", signal: request.signal });
     } catch {
+      request.clear();
       throw new Error("更新文件下载失败");
     }
-    if (response.status < 300 || response.status >= 400) break;
+    if (response.status < 300 || response.status >= 400) { request.clear(); break; }
+    await cancelResponseBody(response);
+    request.clear();
     if (redirects >= maxRedirects) throw new Error("更新文件下载失败");
     const location = response.headers.get("location");
     if (!location) throw new Error("更新文件下载失败");
     current = validateHttpsUrl(new URL(location, current), redirectPolicy);
   }
-  if (response.status < 200 || response.status >= 300 || !response.body) throw new Error("更新文件下载失败");
+  if (response.status < 200 || response.status >= 300 || !response.body) {
+    await cancelResponseBody(response);
+    throw new Error("更新文件下载失败");
+  }
   const declared = Number(response.headers.get("content-length") ?? 0);
   const totalBytes = Number.isSafeInteger(declared) && declared > 0 ? declared : null;
   const maxBytes = options.maxBytes ?? 512 * 1024 * 1024;
-  if (declared > maxBytes) throw new Error("更新文件超过大小限制");
+  if (declared > maxBytes) {
+    await cancelResponseBody(response);
+    throw new Error("更新文件超过大小限制");
+  }
   await mkdir(path.dirname(destination), { recursive: true, mode: 0o700 });
   const temporary = `${destination}.part-${randomUUID()}`;
   let size = 0;
@@ -475,8 +545,10 @@ export async function downloadReleaseAsset(
     hash.update(chunk);
     callback(null, chunk);
   } });
+  const request = beginUpdateRequest(options);
   try {
-    await pipeline(Readable.fromWeb(response.body as import("node:stream/web").ReadableStream), meter, createWriteStream(temporary, { flags: "wx", mode: 0o600 }));
+    const source = Readable.fromWeb(response.body as import("node:stream/web").ReadableStream, { signal: request.signal });
+    await pipeline(source, meter, createWriteStream(temporary, { flags: "wx", mode: 0o600 }));
     const fd = await open(temporary, "r");
     await fd.sync();
     await fd.close();
@@ -484,6 +556,8 @@ export async function downloadReleaseAsset(
   } catch (error) {
     await import("node:fs/promises").then(({ rm }) => rm(temporary, { force: true })).catch(() => undefined);
     throw error instanceof Error && error.message.startsWith("更新文件") ? error : new Error("更新文件下载失败");
+  } finally {
+    request.clear();
   }
   return { size, sha256: hash.digest("hex") };
 }
diff --git a/systemd/tallynote-update.service b/systemd/tallynote-update.service
index aa8ee4e..8333261 100644
--- a/systemd/tallynote-update.service
+++ b/systemd/tallynote-update.service
@@ -1,8 +1,5 @@
 [Unit]
 Description=TallyNote privileged release updater
-After=network-online.target
-Wants=network-online.target
-
 [Service]
 Type=oneshot
 User=root
@@ -11,10 +8,12 @@ WorkingDirectory=/opt/tallynote/current
 EnvironmentFile=-/etc/tallynote/tallynote.env
 ExecStart=/usr/local/libexec/tallynote-update-runner
 Environment=PATH=/usr/sbin:/usr/bin:/sbin:/bin
+# The runner consumes queued requests immediately and applies its own bounded
+# phase timeouts while keeping full CLI diagnostics in the runner log.
 # Downloads, archive validation and data backups can exceed systemd's 90s
 # default start timeout on a slower server. Keep one update job alive long
 # enough to finish or reach its own health-check/recovery path.
-TimeoutStartSec=30min
+TimeoutStartSec=32min
 NoNewPrivileges=true
 # Keep the updater compatible with the same Node/libuv interface discovery
 # path while retaining an explicit socket-family allowlist.
diff --git a/systemd/tallynote.env.example b/systemd/tallynote.env.example
index 1cc6d8c..20ca1d0 100644
--- a/systemd/tallynote.env.example
+++ b/systemd/tallynote.env.example
@@ -9,6 +9,7 @@ TALLYNOTE_TIMEZONE=Asia/Shanghai
 TALLYNOTE_UPDATE_STRATEGY=systemd
 TALLYNOTE_UPDATE_METADATA_URL=https://git.awaioi.com/api/v1/repos/awaioi/TallyNote/releases/latest
 TALLYNOTE_UPDATE_ALLOWED_HOSTS=git.awaioi.com
+TALLYNOTE_UPDATE_TIMEOUT_SECONDS=30
 TALLYNOTE_UPDATE_REQUIRE_SIGNATURE=false
 TALLYNOTE_UPDATE_CHECK_COOLDOWN_SECONDS=60
 TALLYNOTE_UPDATE_DOWNLOAD_COOLDOWN_SECONDS=15
diff --git a/tests/update-api.test.ts b/tests/update-api.test.ts
index 384f05a..8e8d6be 100644
--- a/tests/update-api.test.ts
+++ b/tests/update-api.test.ts
@@ -176,6 +176,42 @@ describe("更新 API", () => {
     expect(ownDetail.json().job.errorMessage).toBe("更新失败，请查看服务器日志或重试");
   });
 
+  it("取消任务按管理员隔离，并只删除匹配任务的请求文件", async () => {
+    const owner = await login("cancel-owner");
+    const other = await login("cancel-other");
+    const ownerId = (database.sqlite.prepare("SELECT id FROM admins WHERE username=?").get("cancel-owner") as { id: string }).id;
+    const otherId = (database.sqlite.prepare("SELECT id FROM admins WHERE username=?").get("cancel-other") as { id: string }).id;
+    const now = Date.now();
+    const ownerJobId = randomUUID();
+    const otherJobId = randomUUID();
+    const insert = database.sqlite.prepare(`
+      INSERT INTO update_jobs(id, admin_id, operation, status, version, platform, asset_url, created_at, updated_at)
+      VALUES (?, ?, 'download', 'queued', '1.3.0', ?, 'https://updates.example/update.tar.gz', ?, ?)
+    `);
+    insert.run(ownerJobId, ownerId, detectPlatform().target, now, now);
+    insert.run(otherJobId, otherId, detectPlatform().target, now + 1, now + 1);
+    await import("node:fs/promises").then(({ writeFile }) => writeFile(config.updateRequestPath, JSON.stringify({ jobId: otherJobId }), { encoding: "utf8", mode: 0o600 }));
+
+    const ownerCancel = await app.inject({
+      method: "POST", url: "/api/update/cancel",
+      headers: { origin: config.publicOrigin, cookie: owner.cookies, "x-csrf-token": owner.csrf },
+      payload: { jobId: ownerJobId },
+    });
+    expect(ownerCancel.statusCode).toBe(200);
+    expect((database.sqlite.prepare("SELECT status FROM update_jobs WHERE id=?").get(ownerJobId) as { status: string }).status).toBe("cancelled");
+    expect((database.sqlite.prepare("SELECT status FROM update_jobs WHERE id=?").get(otherJobId) as { status: string }).status).toBe("queued");
+    expect(existsSync(config.updateRequestPath)).toBe(true);
+
+    const otherCancel = await app.inject({
+      method: "POST", url: "/api/update/cancel",
+      headers: { origin: config.publicOrigin, cookie: other.cookies, "x-csrf-token": other.csrf },
+      payload: {},
+    });
+    expect(otherCancel.statusCode).toBe(200);
+    expect((database.sqlite.prepare("SELECT status FROM update_jobs WHERE id=?").get(otherJobId) as { status: string }).status).toBe("cancelled");
+    expect(existsSync(config.updateRequestPath)).toBe(false);
+  });
+
   it("应用前重新校验失败时写入失败审计", async () => {
     const session = await login("update-audit");
     globalThis.fetch = (async () => new Response("upstream unavailable", { status: 503 })) as typeof fetch;
diff --git a/tests/update.test.ts b/tests/update.test.ts
index 8023991..3a4cbcb 100644
--- a/tests/update.test.ts
+++ b/tests/update.test.ts
@@ -286,8 +286,27 @@ describe("更新安全工具", () => {
       expect(await readFile(path.join(config.currentLink, "dist", "marker"), "utf8")).toBe("new");
       const row = database.sqlite.prepare("SELECT operation, status FROM update_jobs WHERE id=?").get(jobId);
       expect(row).toEqual({ operation: "apply", status: "applying" });
-      finalizeUpdateJob(database.sqlite, jobId, "failed");
-      expect(database.sqlite.prepare("SELECT status FROM update_jobs WHERE id=?").get(jobId)).toEqual({ status: "failed" });
+      finalizeUpdateJob(database.sqlite, jobId, "failed", "健康检查失败（自定义）");
+      expect(database.sqlite.prepare("SELECT status, error_message AS errorMessage FROM update_jobs WHERE id=?").get(jobId)).toEqual({ status: "failed", errorMessage: "健康检查失败（自定义）" });
+      finalizeUpdateJob(database.sqlite, jobId, "failed", "第二次 finalize 不应覆盖原消息");
+      expect(database.sqlite.prepare("SELECT status, error_message AS errorMessage FROM update_jobs WHERE id=?").get(jobId)).toEqual({ status: "failed", errorMessage: "健康检查失败（自定义）" });
+      expect(database.sqlite.prepare("SELECT COUNT(*) AS count FROM audit_events WHERE action='update.failed' AND target_id=?").get(jobId)).toEqual({ count: 1 });
+      const defaultJobId = randomUUID();
+      database.sqlite.prepare(`
+        INSERT INTO update_jobs(id, operation, status, version, platform, asset_url, created_at, updated_at)
+        VALUES (?, 'apply', 'applying', '1.3.0', ?, ?, ?, ?)
+      `).run(defaultJobId, detectPlatform().target, "https://updates.example/" + assetName, now, now);
+      finalizeUpdateJob(database.sqlite, defaultJobId, "failed", "");
+      expect(database.sqlite.prepare("SELECT error_message AS errorMessage FROM update_jobs WHERE id=?").get(defaultJobId)).toEqual({ errorMessage: "新版本健康检查失败，已恢复上一版本" });
+      const completedJobId = randomUUID();
+      database.sqlite.prepare(`
+        INSERT INTO update_jobs(id, operation, status, version, platform, asset_url, created_at, updated_at)
+        VALUES (?, 'apply', 'completed', '1.3.0', ?, ?, ?, ?)
+      `).run(completedJobId, detectPlatform().target, "https://updates.example/" + assetName, now, now);
+      finalizeUpdateJob(database.sqlite, completedJobId, "completed");
+      expect(database.sqlite.prepare("SELECT COUNT(*) AS count FROM audit_events WHERE action='update.completed' AND target_id=?").get(completedJobId)).toEqual({ count: 0 });
+      expect(() => finalizeUpdateJob(database.sqlite, completedJobId, "failed", "不能降级已完成任务")).toThrow("更新任务状态不允许完成");
+      expect(database.sqlite.prepare("SELECT status FROM update_jobs WHERE id=?").get(completedJobId)).toEqual({ status: "completed" });
     } finally {
       globalThis.fetch = previousFetch;
       if (database) database.sqlite.close();
@@ -385,7 +404,7 @@ describe("更新安全工具", () => {
     }
   });
 
-  it("队列任务有新请求标记时可被重新检查，标记过期后才回收", async () => {
+  it("队列任务有匹配请求标记时保留到租约过期，过期后才回收", async () => {
     const root = await mkdtemp(path.join(tmpdir(), "tallynote-update-queued-marker-"));
     let database: ReturnType<typeof openDatabase> | undefined;
     try {
@@ -412,12 +431,14 @@ describe("更新安全工具", () => {
       const now = Date.now();
       await utimes(config.updateRequestPath, new Date(now), new Date(now));
 
-      expect(reconcileOrphanedUpdateJobs(database.sqlite, config, now)).toBe(1);
-      expect(database.sqlite.prepare("SELECT status FROM update_jobs WHERE id=?").get(jobId)).toEqual({ status: "failed" });
-      await expect(stat(config.updateRequestPath)).rejects.toThrow();
+      // The DB row is old, but the request marker is fresh and names this
+      // exact job. Keep it queued while systemd has a chance to consume it.
+      expect(reconcileOrphanedUpdateJobs(database.sqlite, config, now)).toBe(0);
+      expect(database.sqlite.prepare("SELECT status FROM update_jobs WHERE id=?").get(jobId)).toEqual({ status: "queued" });
+      await expect(stat(config.updateRequestPath)).resolves.toBeTruthy();
 
       const expiredNow = now + ORPHANED_UPDATE_TIMEOUT_MS + 1;
-      expect(reconcileOrphanedUpdateJobs(database.sqlite, config, expiredNow)).toBe(0);
+      expect(reconcileOrphanedUpdateJobs(database.sqlite, config, expiredNow)).toBe(1);
       expect(database.sqlite.prepare("SELECT status FROM update_jobs WHERE id=?").get(jobId)).toEqual({ status: "failed" });
       await expect(stat(config.updateRequestPath)).rejects.toThrow();
     } finally {
diff --git a/web-next/src/pages/update/UpdatePage.tsx b/web-next/src/pages/update/UpdatePage.tsx
index f16f8b1..f7de0e4 100644
--- a/web-next/src/pages/update/UpdatePage.tsx
+++ b/web-next/src/pages/update/UpdatePage.tsx
@@ -248,22 +248,48 @@ export default function UpdatePage({
   const announced = useRef<string | null>(null);
   const checkInFlight = useRef(false);
   const actionInFlight = useRef(false);
+  const cancelInFlight = useRef(false);
+  const loadInFlight = useRef(false);
   const disconnected = useRef(false);
   const recoveredNotice = useRef(false);
 
   const info = liveInfo;
 
-  const load = async () => {
-    setLoading(true);
+  const mergeInfo = (incoming: UpdateInfo, preserveJob = false) => {
+    setLiveInfo((current) => {
+      if (!current) return incoming;
+      const next = {
+        ...current,
+        ...incoming,
+        // A check response describes the release, but must not erase the job
+        // that is already being displayed while that check is in flight.
+        job: preserveJob
+          ? (current.job ?? incoming.job)
+          : (!Object.prototype.hasOwnProperty.call(incoming, "job") ? current.job : incoming.job),
+      };
+      // Some status/check responses are intentionally partial. Keep fields
+      // from the last successful response when a field is omitted.
+      if (!Object.prototype.hasOwnProperty.call(incoming, "latest")) next.latest = current.latest;
+      if (!Object.prototype.hasOwnProperty.call(incoming, "checkedAt")) next.checkedAt = current.checkedAt;
+      if (!Object.prototype.hasOwnProperty.call(incoming, "strategy")) next.strategy = current.strategy;
+      return next;
+    });
+  };
+
+  const load = async (showLoading = true) => {
+    if (loadInFlight.current) return;
+    loadInFlight.current = true;
+    if (showLoading) setLoading(true);
     setError("");
     try {
       const res = await api<UpdateInfo>("/api/update/status");
-      setLiveInfo(res);
+      mergeInfo(res);
       updateInfoCache = res;
     } catch (e) {
       setError((e as Error).message);
     } finally {
-      setLoading(false);
+      if (showLoading) setLoading(false);
+      loadInFlight.current = false;
     }
   };
 
@@ -293,7 +319,8 @@ export default function UpdatePage({
     return () => window.clearInterval(timer);
   }, [restartAt]);
 
-  // Live polling effect: only poll when active job exists
+  // Live polling effect for an active job. Completed responses are refreshed
+  // once so latest/checkedAt/strategy stay current; other terminal states stay visible.
   useEffect(() => {
     const shouldPoll = Boolean(
       job && (pollableStatuses.has(job.status) || (job.status === "staged" && job.operation === "apply"))
@@ -326,23 +353,53 @@ export default function UpdatePage({
           setReloadReady(true);
           notify?.("系统升级完成，请刷新页面", "success");
         }
-        if (
+        if (result.job.status === "completed") {
+          void load(false);
+        } else if (
           pollableStatuses.has(result.job.status) ||
           (result.job.status === "staged" && result.job.operation === "apply")
         ) {
           schedule(1500);
         }
-      } catch {
+      } catch (caught) {
         if (disposed) return;
+        const status = caught instanceof ApiError ? caught.status : 0;
+        const message = caught instanceof Error ? caught.message : "读取更新任务状态失败";
+        if (status === 404) {
+          setPollError("更新任务已结束，正在刷新状态。");
+          void load(false);
+          return;
+        }
+        if (status === 401) {
+          setPollError("登录已失效，请重新登录。");
+          return;
+        }
+        if (status === 403) {
+          setPollError("没有权限读取更新任务状态。");
+          return;
+        }
+
         failures += 1;
-        disconnected.current = true;
+        disconnected.current = status === 0 || status === 408;
         recoveredNotice.current = false;
-        setPollError(
-          `服务正在平滑重启${
-            restartSeconds !== null ? `，预计 ${restartSeconds} 秒后恢复` : "，页面正在自动探活重试"
-          }。升级任务仍在后台安全执行。`
-        );
-        schedule(Math.min(1500 * 2 ** Math.min(failures, 3), 10_000));
+        if (status === 409) {
+          setPollError(`${message}，正在刷新状态。`);
+          void load(false);
+          return;
+        }
+        if (status === 429) {
+          setPollError(`${message}，稍后继续同步。`);
+        } else if (status === 408) {
+          setPollError("读取更新任务状态超时，正在重试。");
+        } else if (status === 0) {
+          setPollError("更新服务连接异常，正在重试。");
+        } else {
+          setPollError(`${message}，正在重试。`);
+        }
+        const retryAfter = caught instanceof ApiError && caught.retryAfter
+          ? Math.max(1000, caught.retryAfter * 1000)
+          : Math.min(1500 * 2 ** Math.min(failures, 3), 10_000);
+        schedule(retryAfter);
       }
     };
     void poll();
@@ -352,6 +409,42 @@ export default function UpdatePage({
     };
   }, [job?.id, job?.status, job?.operation, notify]);
 
+  // With no visible job, make a low-frequency status request so a task created
+  // elsewhere can still appear without creating a request storm.
+  useEffect(() => {
+    if (job) return;
+    let timer: number | undefined;
+    let disposed = false;
+    const discover = () => {
+      if (disposed || document.visibilityState !== "visible") return;
+      void load(false);
+    };
+    const schedule = () => {
+      if (disposed) return;
+      if (timer !== undefined) window.clearTimeout(timer);
+      timer = window.setTimeout(() => {
+        discover();
+        schedule();
+      }, 5000);
+    };
+    const onVisibilityChange = () => {
+      if (document.visibilityState === "visible") {
+        discover();
+        schedule();
+      } else if (timer !== undefined) {
+        window.clearTimeout(timer);
+        timer = undefined;
+      }
+    };
+    if (document.visibilityState === "visible") schedule();
+    document.addEventListener("visibilitychange", onVisibilityChange);
+    return () => {
+      disposed = true;
+      if (timer !== undefined) window.clearTimeout(timer);
+      document.removeEventListener("visibilitychange", onVisibilityChange);
+    };
+  }, [job?.id, job?.status, job?.operation]);
+
   // Check update handler
   const check = async () => {
     if (checkInFlight.current) return;
@@ -359,7 +452,8 @@ export default function UpdatePage({
     setChecking(true);
     setError("");
     try {
-      setLiveInfo(await api<UpdateInfo>("/api/update/check", { method: "POST" }));
+      const result = await api<UpdateInfo>("/api/update/check", { method: "POST" });
+      mergeInfo(result, true);
       notify?.("版本检查完成", "info");
     } catch (e) {
       if (e instanceof ApiError && e.status === 429) {
@@ -375,7 +469,8 @@ export default function UpdatePage({
 
   // Cancel queued job handler
   const cancelJob = async () => {
-    if (cancelling) return;
+    if (cancelInFlight.current || !job?.id) return;
+    cancelInFlight.current = true;
     setCancelling(true);
     try {
       await api("/api/update/cancel", { method: "POST", body: JSON.stringify({ jobId: job?.id }) });
@@ -387,6 +482,7 @@ export default function UpdatePage({
       notify?.((e as Error).message, "error");
     } finally {
       setCancelling(false);
+      cancelInFlight.current = false;
     }
   };
 
@@ -487,7 +583,7 @@ export default function UpdatePage({
     if (!job) return 0;
     if (job.status === "completed" || job.status === "staged") return 100;
     if (job.status === "downloading") {
-      if (!job.sizeBytes || !job.downloadedBytes) return 10;
+      if (!job.sizeBytes || !job.downloadedBytes) return 0;
       return Math.min(99, Math.max(1, Math.round((job.downloadedBytes / job.sizeBytes) * 100)));
     }
     if (job.status === "verifying") return 99;