According to www.gnugk.org/ some keepalive settings should be changed to improve reliability - it will enable keep alive functionality (checking if the connection is established and valid) and, by decreasing times and interval - will make detection of broken connections faster.
# sysctl -w net.ipv4.tcp_keepalive_time="60" net.ipv4.tcp_keepalive_time = 60 # sysctl -w net.ipv4.tcp_keepalive_probes="3" net.ipv4.tcp_keepalive_probes = 3 # sysctl -w net.ipv4.tcp_keepalive_intvl="90" net.ipv4.tcp_keepalive_intvl = 90
