I just found a solution to a problem I've been having but would like to run it by my fellow Spiceheads to see if I am missing anything. Prior to finding what ultimately worked, I googled just about every possible combination of keywords looking for what I thought would have been a fairly textbook scenario, but to no avail.
I have a small test network running OSPF between 3 routers and a pfSense box performing NAT/firewall duties. pfSense is running Quagga OSPF and is redistributing the default route. Within the LAN, I can ping to/from any of the subnets, but can only ping out to the internet from the subnet local to the pfSense LAN interface. After reading the internet, I discovered that pfSense's default “Automatic Outbound NAT rule generation” will only generate mappings for each interfaces subnet and/or any statically routed networks. In my scenario, everything not directly connected is learned via OSPF. I switched to “Manual Outbound NAT rule generation” and created a mapping for the entire 10.0.0.0/8 network and now everything seems to be working fine.
Is this the best/only solution here? Is there a better way to approach? Like I said, I'm just surprised I couldn't find this solution out there on the web.
I've attached a diagram below of the network for reference