fix(tunnel): add timeout to keepAliveLoop to detect dead connections after sleep/wake#581
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fix(tunnel): add timeout to keepAliveLoop to detect dead connections after sleep/wake#581ncodespot wants to merge 2 commits into
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…after sleep/wake SendRequest blocks indefinitely on a dead TCP connection (e.g. after OS sleep/wake where no RST/FIN is received). Run it in a goroutine and use select with time.After(KeepAlive) as a deadline. On timeout, close the SSH connection so that blocked OpenChannel calls are also unblocked and the client can reconnect. Also add unit tests for keepAliveLoop and an E2E test with a freezable TCP proxy that simulates the sleep/wake scenario end-to-end. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This was referenced Jun 12, 2026
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- race keepalive SendRequest against a timer (default: keepalive interval, override with CHISEL_PING_TIMEOUT) and close the ssh conn on timeout so the client reconnect loop kicks in - replace the time.Sleep ping loop with a stoppable ticker that exits when the connection closes - add unit tests (mock ssh.Conn) and an e2e blackhole-link test, adapted from PR #581 with its broken tcpEcho assertion fixed Closes md task 1 Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
jpillora
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- closed 11 superseded dependabot PRs (#448 #449 #450 #451 #467 #470 #478 #496 #513 #516 #517) — deps updated via #568/#578 - closed duplicate keepalive PRs #488/#442 with thanks (#581's approach won, implemented in task 1) - closed keepalive issues #445/#560 (fixed by task 1, ships next release); #585/#541 were already closed - left #504/#550/#485 for task 22 and #561/#498 for task 23, as those tasks deliver the fixes that close them - filed task 35: decide dependabot grouped updates vs renovate Closes md task 21 Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Problem
After OS sleep/wake, port forwarding becomes unresponsive even with
--keepaliveset. Root cause:SendRequest("ping")inkeepAliveLoopblocks indefinitely on a dead TCP connection. When the system wakes from sleep, the TCP connection is stale but no RST/FIN has been received, so the OS has not yet detected failure. Both the keepalive ping and concurrentOpenChannelcalls block until TCP retransmit timeout fires (potentially 15+ minutes).Fix
Run
SendRequestin a goroutine and race it againsttime.After(KeepAlive). If no pong is received within the keepalive interval, treat it as a dead connection and callsshConn.Close(). This also unblocks any goroutines stuck inOpenChannelon the same connection, triggering reconnection.With
--keepalive 15s, worst-case detection is now ~30s (15s sleep + 15s ping timeout) instead of indefinite.Tests
share/tunnel/tunnel_keepalive_test.go): mockssh.ConnwhoseSendRequestblocks forever; assertsClose()is called within 2×keepalive.test/e2e/keepalive_test.go): freezable TCP proxy between client and server simulates sleep/wake (silent packet drop, no RST); verifies tunnel recovers automatically.