The following I believe are the ports that fog uses:
FTP – tcp 20,21
SSH – tcp 22
TFTP – udp 69
HTTP(s) – tcp 80,443
Portmap – tcp/udp 111
NFS – tcp/udp 2049
Transfer ports – tcp/udp 1024 – 65535
Depending on where your firewall is located you may not need to make changes to it though. For example if it is out on the DMZ it shouldn’t matter. You will need to configure DHCP in your switches though if not already done so. [url]http://www.fogproject.org/wiki/index.php/Modifying_existing_DHCP_server_to_work_with_FOG[/url]