Projects / OpenSSH Heartbeat/Watchdog Patch

OpenSSH Heartbeat/Watchdog Patch

OpenSSH Heartbeat/Watchdog Patch adds a heartbeat (keepalive) function to ssh(1). If the output channel has been silent for more than a specified time, a null message (SSH_MSG_IGNORE) is sent to the server as a heartbeat. The heartbeat is useful for keeping connections over IP masquerade/NAT boxes, firewalls, etc. This patch also adds a watchdog timeout function to sshd(8). The combination of the heartbeat and the watchdog timeout is very useful for detecting a link which is down over unreliable connections such as a wireless network.

Operating Systems

Recent releases

  •  01 Oct 2006 11:24

    Release Notes: This version was adapted to OpenSSH 4.4p1. The documentation patch has been incorporated.

    •  12 Mar 2005 06:24

      Release Notes: This version was adapted for OpenSSH 4.0p1.

      •  17 Oct 2004 20:21

        Release Notes: Adapted to OpenSSH 3.9p1.

        •  30 Oct 2003 18:23

          Release Notes: This patch is updated to apply cleanly against OpenSSH 3.7.1p1 and p2.

          •  21 Jun 2003 02:05

            No changes have been submitted for this release.

            Recent comments

            12 Mar 2005 01:29 hgot

            Re: usefulness ?
            This patch might be useless if you are lucky enough to have no SSH1 server around you. More importantly, this patch (especially the latter half part) was originally developed to be used with the

            Authenticating Gateway.

            11 Mar 2005 23:24 mmuman

            usefulness ?
            I don't have problems anymore with my NAT router after I added "-o ServerAliveInterval=60" to the ssh command line setting up the tunnel here (using 3.9p1). Is that thing really needed ?


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