Maximum segment lifetime
Maximum segment lifetime is the time a TCP segment can exist in the internetwork system. It is arbitrarily defined to be long.
The Maximum Segment Lifetime value is used to determine the TIME_WAIT interval
The command that can be used on many Unix systems to determine the TIME_WAIT interval is:
ndd -get /dev/tcp tcp_time_wait_interval
60000 is a common value.
On FreeBSD systems this description and value can be checked by the command sysctl:
sysctl -d net.inet.tcp.msl
sysctl net.inet.tcp.msl
which gets the result:
net.inet.tcp.msl: Maximum segment lifetime
net.inet.tcp.msl: 30000
On some Linux systems, this value can be checked by either of the commands below:
sysctl net.ipv4.tcp_fin_timeout
cat /proc/sys/net/ipv4/tcp_fin_timeout
