ClientAliveInterval

[Aris Adamantiadis]

Hello Sayan,

As I told to Sabaya, this will be corrected in libssh soon. This problem
was not spotted because the ClientAliveInterval was not a default
parameter of most systems.

Peter, I think Sayan had understood your message the first time.

Best regards,

Aris



Sayan Chaliha a écrit :
> @Damien:
> 
> Yes, well, I understand that. But I am experiencing some weird behavior with
> libssh... So I was wondering whether it had anything to do with not replying
> to keepalive at openssh.com
> 
> Here's what I'm experiencing:
> -- When the app gets disconnected from the OpenSSH 4.3 server, it tries to
> reconnect.
> -- Reconnection and authorization are successful, but libssh fails when
> trying to open a new channel (with some obscure 'unrecognized packet'
> message).
> -- This continues until the ClientAliveInterval has expired.
> 
> Anyway, thanks for all the help. I'm now sure that the problem in not with
> my application but rather with libssh. I've gotten in touch with them (ie,
> the developers of libssh) to have this issue solved.
> 
> Thanks again for your time!
> 
> On Sat, Feb 27, 2010 at 5:59 AM, Damien Miller <djm at mindrot.org> wrote:
> 
>> On Fri, 26 Feb 2010, Sayan Chaliha wrote:
>>
>>> @Damien, could you also tell me what would happen if the client didn't
>>> respond to that request, and instead tried to create new session and
>> channel
>>> afresh? Would the server send the same message again?
>> A client that is compliant with the protocol _must_ respond, even just to
>> say "I have no idea what this command is". Any response will reset the
>> keepalive timer.
>>
>>> On Fri, Feb 26, 2010 at 12:40 PM, Damien Miller <djm at mindrot.org> wrote:
>>>
>>>> On Fri, 26 Feb 2010, Sayan Chaliha wrote:
>>>>
>>>>> Hi,
>>>>>
>>>>> I am having some trouble with the ClientAliveInterval server setting.
>> My
>>>>> (C++) application fails to start an SSH channel to an OpensSSH server
>>>> within
>>>>> this time-out period if it doesn't reply correctly to this
>> 'keep-alive'
>>>>> no-op that is sent by the server. How is this no-op handled? I am
>> using
>>>> the
>>>>> libssh client library, and I could find no references on how to
>> handle
>>>> this.
>>>>
>>>> Client aliver interval is implemented by sending a global or channel
>>>> request of type "keepalive at openssh.com" with want-reply turned on.
>>>> You shouldn't need to implement anything for this to work - a client
>>>> should return SSH2_MSG_REQUEST_FAILURE if it doesn't implement this
>> request
>>>> type and that should be enough to reset the keepalive watchdog timer.
>>>>
>>>> If you would like to explicitly support it, you can just send an
>>>> approprate SSH2_MSG_REQUEST_SUCCESS (global request) or
>>>> SSH2_MSG_CHANNEL_SUCCESS (channel request) message, but this is purely
>>>> optional.
>>>>
>>>> -d
>>>>
>>>
>>>
>>> --
>>> Regards,
>>> Sayan Chaliha
>>> Webyog Softworks Private Limited
>>> 2nd Floor, Novel Team Building
>>> #10, 100 Feet Ring Road
>>> BTM Layout 1st Stage
>>> Bangalore - 560068
>>>
>>> +91-9743357501
>>> _______________________________________________
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>>> openssh-unix-dev at mindrot.org
>>> https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
>>>
> 
> 
>