vonskippy wrote:
I guess the snarky answer would be "It can't hurt and it might help".
I can't disagree with that statement.
But for me, it's a philosophical issue. I think the idea of a software firewall (for what most people use it for) is silly. If a port isn't open then no connection can be made unless the attacker has a really really cool exploit.
I only have port 80 and port 22 open, with Fail2Ban ready and waiting for failed SSH login attempts. (It's killed someone since today too

). Maybe even port knocking could be set up on port 22 for added security.
In my case, the only advantage I can readily see to using a firewall is that a RST packet won't be sent when an attempted connection to a closed port is made. But as I write I have realised another advantage. A firewall can help if you have services that run at startup that open ports, and you stop them manually, and the system either reboots and they start again or they start again magically (which I've seen happen on Ubuntu). But with some diligence from the administrator this shouldn't be a problem either. But since realising that no one is perfect and mistakes can be made, lapses in memory, tired sysadmin, or even random bugs in the system, might as well use the firewall and forget about it.
EDIT: If you have requirements to allow/deny traffic from certain sources, then a firewall would definitely be helpful.
Mind you, I think hardware firewalls on networks are very useful since they can control the connections between networks.
_________________
If all else fails, reboot...
PHP Tutorials and MySQL Tutorials