Comments on: Keeping Your SSH Connection Alive http://pthree.org/2008/04/16/keeping-your-ssh-connection-alive/ Linux. GNU. Freedom. Sun, 14 Mar 2010 14:51:42 +0000 hourly 1 http://wordpress.org/?v=3.0-alpha By: dr. x http://pthree.org/2008/04/16/keeping-your-ssh-connection-alive/#comment-110072 dr. x Sat, 18 Jul 2009 03:12:14 +0000 http://pthree.org/?p=566#comment-110072 hmmm... i *think* (am no expert) you really would want to turn OFF TcpKeepAlive, not turn it on. If you have it ON the client/server will notice when the connection is unresponsive and... as seems to be implied by the man page, close the socket. Which is what some people find annoying... as expressed in the man page entry below. from the man page for ssh_config: TCPKeepAlive Specifies whether the system should send TCP keepalive messages to the other side. If they are sent, death of the connection or crash of one of the machines will be properly noticed. This option only uses TCP keepalives (as opposed to using ssh level keepalives), so takes a long time to notice when the connection dies. As such, you probably want the ServerAliveInterval option as well. However, this means that connections will die if the route is down temporarily, and some people find it annoying. The default is “yes” (to send TCP keepalive messages), and the client will notice if the network goes down or the remote host dies. This is important in scripts, and many users want it too. To disable TCP keepalive messages, the value should be set to “no”. hmmm… i *think* (am no expert) you really would want to turn OFF TcpKeepAlive, not turn it on.

If you have it ON the client/server will notice when the connection is unresponsive and… as seems to be implied by the man page, close the socket. Which is what some people find annoying… as expressed in the man page entry below.

from the man page for ssh_config:

TCPKeepAlive
Specifies whether the system should send TCP keepalive messages
to the other side. If they are sent, death of the connection or
crash of one of the machines will be properly noticed. This
option only uses TCP keepalives (as opposed to using ssh level
keepalives), so takes a long time to notice when the connection
dies. As such, you probably want the ServerAliveInterval option
as well. However, this means that connections will die if the
route is down temporarily, and some people find it annoying.

The default is “yes” (to send TCP keepalive messages), and the
client will notice if the network goes down or the remote host
dies. This is important in scripts, and many users want it too.

To disable TCP keepalive messages, the value should be set to
“no”.

]]> By: GNUWIX http://pthree.org/2008/04/16/keeping-your-ssh-connection-alive/#comment-109863 GNUWIX Tue, 24 Mar 2009 06:19:51 +0000 http://pthree.org/?p=566#comment-109863 So, with the TCPKeepAlive option passed to SSH, the SSH client will send an encrypted packet to the SSH server, keeping your TCP connection up and running. This is inaccurate.. This is a TCP option and will not send "an encrypted packet" Otherwise pretty good post thank you So, with the TCPKeepAlive option passed to SSH, the SSH client will send an encrypted packet to the SSH server, keeping your TCP connection up and running.

This is inaccurate.. This is a TCP option and will not send “an encrypted packet”

Otherwise pretty good post thank you

]]> By: Hans http://pthree.org/2008/04/16/keeping-your-ssh-connection-alive/#comment-97872 Hans Thu, 17 Apr 2008 16:41:20 +0000 http://pthree.org/?p=566#comment-97872 autossh has its place, but its job is to automate reconnecting in the event of a disconnect, not keeping a connection alive. autossh has its place, but its job is to automate reconnecting in the event of a disconnect, not keeping a connection alive.

]]> By: Kurt http://pthree.org/2008/04/16/keeping-your-ssh-connection-alive/#comment-97817 Kurt Thu, 17 Apr 2008 12:16:56 +0000 http://pthree.org/?p=566#comment-97817 What about using autossh? What about using autossh?

]]> By: Aaron http://pthree.org/2008/04/16/keeping-your-ssh-connection-alive/#comment-97704 Aaron Wed, 16 Apr 2008 21:45:59 +0000 http://pthree.org/?p=566#comment-97704 @Bjørn Grønbæk- It does. Add either of those options to your ~/.ssh/config file. The sshfs utility reads that file, and adds the options to the connection, as sshfs just just an ssh directory mounted to a local dir on your filesystem. @Bjørn Grønbæk- It does. Add either of those options to your ~/.ssh/config file. The sshfs utility reads that file, and adds the options to the connection, as sshfs just just an ssh directory mounted to a local dir on your filesystem.

]]> By: Steve http://pthree.org/2008/04/16/keeping-your-ssh-connection-alive/#comment-97695 Steve Wed, 16 Apr 2008 20:37:43 +0000 http://pthree.org/?p=566#comment-97695 excellent! excellent!

]]> By: Bjørn Grønbæk http://pthree.org/2008/04/16/keeping-your-ssh-connection-alive/#comment-97673 Bjørn Grønbæk Wed, 16 Apr 2008 18:45:24 +0000 http://pthree.org/?p=566#comment-97673 Thanks man. I'm having the exact same problem here at University of Southern Denmark. Stupid network... It really screws up your system if you mount a remote folder with sshfs, and the connection is terminated by inactivity. It would be nice if sshfs had some option just like those above. But your advice is a great help anyway. Thanks man. I’m having the exact same problem here at University of Southern Denmark. Stupid network…

It really screws up your system if you mount a remote folder with sshfs, and the connection is terminated by inactivity. It would be nice if sshfs had some option just like those above. But your advice is a great help anyway.

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