Re[2]: SSH-connections hanging (IP-filter related?)

From: Marius Huse Jacobsen (
Date: 12/16/03

  • Next message: Atro Tossavainen: "Re: Porting SSH (VxWorks)"
    Date: Mon, 15 Dec 2003 16:49:52 -0800
    To: Rob De Langhe <>

    Hash: SHA1

    Hello Rob,

    Wednesday, December 10, 2003, 10:58:55 PM, you wrote:

    RDL> Hi,

    RDL> The connection from the central
    RDL> server is still ESTABLISHED, and a "truss" on the SSHD program shows a
    RDL> "poll()" that's hanging. Sure on the connecting side (the central server),
    RDL> the "ssh" client is still waiting for the remote end to close the
    RDL> connection. And so my batch jobs hang...

    RDL> We run IP-Filter everywhere, and I noticed a few posts on the Internet that
    RDL> might indicate relationship of this SSH-problem with the fact that IP-filter
    RDL> is controlling the communications.

    If sshd is still running, then I doubt the problem is with ipfilter.

    RDL> I found another hint about the BASH environment variable "huponexit", but
    RDL> that's not relevant either since the remote "bash" completes entirely,
    RDL> including its childs. But its invoking parent, the "sshd" that accepted the
    RDL> connection, is hanging.

    RDL> Any hints/tips ?

    If you can have bash run a logoff command, have it send some signal to
    its parent (sshd) to make it terminate. (kill -9 could kill some
    unflushed buffers as well, while the others *should* work properly in
    this respect)

    I'm not knowledgable about what poll() does, but the best solution
    would probably be to make it succeed.

    - --
    Best regards,


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  • Next message: Atro Tossavainen: "Re: Porting SSH (VxWorks)"

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