Dual NIC Server - Cannot access via Internet [SOLVED]

[ConceptDog]

Hi all,

We've set up a gentoo server with apache, openssh, and samba. It's dual homed with the intent of allowing http and ssh access from inside the building, via LAN and outside the building via internet. Samba is also enabled on the LAN NIC to allow it to join our Win 2k domain and allow file transfer.

Here's the issue we've run into. Web serving / Internet access from within the building works great, however, when we open the ports on the firewall protecting the internet connection, most of the time, we cannot connect via ssh or http. Most of the time being that sometimes we can get a connection, if it's with SSH, it connects and stays connected, with http, we get a few pages, then it starts timing out again.

Packet capture at the router shows that data is getting through, but sometimes, none comes back. If I disable the internal NIC leaving only the internet connected NIC, we seem to be able to make connections and serve pages 100% of the time.

I'm lost as to what to look at next. The server was set up with a hardened kernel, booting to a gentoo kernel hasn't helped. It's not an option to just put all traffic on the internet NIC, as that would involve dual homing everyone in the office to work on it.

Any help or thoughts about what I should try next would be appreciated. Thanks!

[ConceptDog]

Turns out that the problem was with routing when two nics are installed. Following the instructions here:

http://gentoo-wiki.com/TIP_Dual-Homed_Gentoo_Server

Plus adding the correct routing to both tables allowed traffic served to that nic to be returned on that same connection.

Thanks for everything. ^^