I have a fresh install of Ubuntu Server 12.04, I've added a password for the root user so I can type commands a little faster, installed bridge utilities with "sudo apt-get install bridge-utils", I made "eth0" dhcp (which is working correctly), and created a bridge "br0" with a static IP using "eth1" and "eth2". PC #1 and #3 are able to communicate. This is literally all I have done. Now from my understanding since I haven't set up any sort of forwarding to my knowledge these two networks are completely separate, and shouldn't be able to access each other, right?
Apparently not, because PC #2 can SSH into the "br0" IP (192.168.0.10), and PC #1 and #3 can SSH into "eth0" (192.168.0.122). I want "br0", and "eth0" networks separate, and don't understand why, or how this is even happening since I haven't even un-commented the line to forward ipv4 addresses..
*edit* PC #2 cannot access PC #1, or PC #3. Which is fine, and how I'd like it. PC #1, and #3 can't reach PC #2 as well.