jenkinsci/jenkins · error · SocketTimeoutException

Failed to retrieve command result in time: {}

Error message

Failed to retrieve command result in time: {}

What it means

SocketTimeoutException thrown by SSHCLI when channel.waitFor(ClientChannelEvent.CLOSED, 0L) returns a mask containing TIMEOUT. The SSH exec channel did not close within the wait, so no exit status could be obtained for the command.

Source

Thrown at cli/src/main/java/hudson/cli/SSHCLI.java:113

            cf.await();
            try (ClientSession session = cf.getSession()) {
                for (KeyPair pair : provider.getKeys()) {
                    CLI.LOGGER.log(FINE, "Offering {0} private key", pair.getPrivate().getAlgorithm());
                    session.addPublicKeyIdentity(pair);
                }
                session.auth().verify(10000L);

                try (ClientChannel channel = session.createExecChannel(command.toString())) {
                    channel.setIn(new NoCloseInputStream(System.in));
                    channel.setOut(new NoCloseOutputStream(System.out));
                    channel.setErr(new NoCloseOutputStream(System.err));
                    WaitableFuture wf = channel.open();
                    wf.await();

                    Set<ClientChannelEvent> waitMask = channel.waitFor(List.of(ClientChannelEvent.CLOSED), 0L);

                    if (waitMask.contains(ClientChannelEvent.TIMEOUT)) {
                        throw new SocketTimeoutException("Failed to retrieve command result in time: " + command);
                    }

                    Integer exitStatus = channel.getExitStatus();
                    return exitStatus;

                }
            } finally {
                client.stop();
            }
        }
    }

    @SuppressFBWarnings(value = "URLCONNECTION_SSRF_FD", justification = "Client-side code doesn't involve SSRF.")
    private static URLConnection openConnection(URL url) throws IOException {
        return url.openConnection();
    }

    private SSHCLI() {}

View on GitHub (pinned to 2e228ff40b)

Solutions

1. Confirm the command is expected to terminate; if it is long-running, run it asynchronously or increase the effective timeout.
2. Ensure stdin is closed/redirected (</dev/null) so the remote command does not block waiting for input.
3. Check SSH/network health and that the controller is responsive (not GC-thrashing or deadlocked).

Example fix

# before: command may block on stdin
java -jar jenkins-cli.jar -ssh -s jenkins help
# after: close stdin so the channel can terminate
echo '' | java -jar jenkins-cli.jar -ssh -s jenkins help
# or: java -jar jenkins-cli.jar -ssh -s jenkins help </dev/null

// Before running, sanity-check the controller is responsive over SSH
try (ClientSession s = client.connect(UserAuth, host, port).verify(10, TimeUnit.SECONDS).getSession()) {
    s.auth().verify(10000L);
} // reachable; proceed to run the command

try {
    channel.waitFor(List.of(ClientChannelEvent.CLOSED), timeout);
} catch (SocketTimeoutException e) {
    // optionally retry once, then report the command did not finish in time
}

When it happens

Trigger: The remote Jenkins SSH command hangs (long-running operation, waiting on a lock, or prompting for input that never arrives), or the network stalls so the channel never receives EOF/CLOSED.

Common situations: Running a CLI command that triggers a long job/lock on the controller; SSH keepalive not configured so a dead connection lingers; command blocked on stdin that the client never sends/closes.

Related errors

• Unsupported private key file format: key
• Multiple private key pairs N/A: key
• There's no Jenkins running at {}
• expected to see initial zero byte; perhaps you are connectin
• There's no Jenkins running at {}, or is not serving the HTTP

AI-assisted analysis of jenkinsci/jenkins@2e228ff40b (2026-08-14). Data as JSON: /api/errors/80a493113c0731d6. Report an issue: GitHub.