Gergely Buday wrote: > Hi there, > > some of my users use putty to connect to my server via ssh protocol. > After some time they get the above error message, and it could be that > my CentOS-side configuration caused this. Do anybody has experience > with this problem? > it could be a lot of things, including a NAT router's session tracking timing out on an idle session. in their putty configuration, enable 'tcp keep-alives', this is on 'connections', also set the keepalive timer to like 30 seconds.