[TriLUG] How do I clear inactive SSH session

Jeremy Portzer jeremyp at pobox.com
Mon Aug 26 10:00:38 EDT 2002


On Sun, 25 Aug 2002, Jon Carnes wrote:

> Definately!
> 
> Do a quick man of sshd_config
> ===
>    ClientAliveInterval
>         Sets a timeout interval in seconds after which if no data has
>         been received from the client, sshd will send a message through
>         the encrypted channel to request a response from the client.  The
>         default is 0, indicating that these messages will not be sent to
>         the client.  This option applies to protocol version 2 only.
> 
>    ClientAliveCountMax
>         Sets the number of client alive messages (see above) which may be
>         sent without sshd receiving any messages back from the client. If
>         this threshold is reached while client alive messages are being
>         sent, sshd will disconnect the client, terminating the session.
>         It is important to note that the use of client alive messages is
>         very different from KeepAlive (below). The client alive messages
>         are sent through the encrypted channel and therefore will not be
>         spoofable. The TCP keepalive option enabled by KeepAlive is
>         spoofable. The client alive mechanism is valuable when the client
>         or server depend on knowing when a connection has become inac-
>         tive.
> 
>         The default value is 3. If ClientAliveInterval (above) is set to
>         15, and ClientAliveCountMax is left at the default, unresponsive
>         ssh clients will be disconnected after approximately 45 seconds.

Hi,

It strikes me that these options won't do quite what Kevin was looking
for.  A connected client will always respond to the client keep alive
mentioned above, right?  So if the network connection is working fine, but
the *user* is just idle, nothing will ever be disconnected.  The above
options appear to be useful for when the network goes down, or if the
client just "goes away" without closing down the ssh connection.

--Jeremy




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