What does the Broken pipe message mean in an SSH session?

Question

Sometimes my SSH session disconnects with a Write failed: Broken pipe message. What does it mean? And how can I keep my session open?

I know about screen, but that's not the answer I'm looking for. I think this is a sshd config option.

Answer 1

It's possible that your server closes connections that are idle for too long. You can update either your client (ServerAliveInterval) or your server (ClientAliveInterval)

 ServerAliveInterval
         Sets a timeout interval in seconds after which if no data has
         been received from the server, ssh(1) will send a message through
         the encrypted channel to request a response from the server.  The
         default is 0, indicating that these messages will not be sent to
         the server.  This option applies to protocol version 2 only.

 ClientAliveInterval
         Sets a timeout interval in seconds after which if no data has
         been received from the client, sshd(8) 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.

To update your server (and restart your sshd)

echo "ClientAliveInterval 60" | sudo tee -a /etc/ssh/sshd_config

Or client-side:

echo "ServerAliveInterval 60" >> ~/.ssh/config 

Answer 2

To make a complementary of Gert's answer, I wrote this article to solve this SSH issue: http://nextspaceship.com/2011/09/how-to-solve-broken-pipe-message-in-ssh-session/ Sometimes the network is unstable, so we need a script to auto restart the ssh session, don't we?

Answer 3

It usually means that your network (TCP) connection was reset. E.g. your internet provider reconnected you or something like this.

Answer 4

Another cause for the "Broken Pipe message" is that another machine is attempting use the same IP as your host.

A simple way to test if someone else is using that IP:

1. Turn off your host
2. ping the same IP to see if another machine is using that IP

To find out which machines are on your network, you can use this Unix & Linux question title: How to find what other machines are connected to the local network.