Sometimes SSH sessions die. At work I usually have several ssh sessions with a number of servers, and depending on the configuration of some intermediate router/firewall some TCP sessions get closed after a little while, the SSH sessions die and you have to log back in again.

To prevent this you can instruct sshd to implement some kind of keepalive mechanism preventing the TCP sessions from dying, by including these options on the sshd_config file:

Via Applesfera I’ve learnt about two applications developed by Hanynet that allow you to manage the internal firewall on MacOS X Leopard:

• NoobProof, easier to use for the average user, and
• WaterRoof (cool name XD), more detailed, for the technically-savvy

Very useful.