ethernet redundancy

[SxN]

Hi All,

I am trying to accomplish the following: a server needs to provide it's services via internet. A router with two inputs (homing, I guess) will handle two ISP's. The server will have two NICs. One of them should have a static LAN IP, the other one should stay idle. That IP+port will be used by the router for port forwarding. A script should check once in a while that the server still can talk to the router (ping). On failure (maybe some retrys?), it should inactivate the first NIC and activate the second one, with the same IP. If it pings, than it takes care of the workload, and sends an email to the administrator regarding the failure of the first line. If it fails pinging, it concludes that it looks like a router issue, and using as modem sends an urgent message (pager?) to the administrator, plus an email. I would also like to have a way to check once in a while that both ISPs are there (or, which one isn't).

Has anyone done something similar before?

Any pointers are welcomed.

Thanks,
SxN

[joyo222]

wouldn't just bonding the NICs do what you want? use the bonding module:

http://gentoo-wiki.com/HOWTO_Setup_Bonded_ethernet_adapters
http://linux-net.osdl.org/index.php/Bonding
/usr/src/linux/Documentation/networking/bonding.txt

you will want mode=1 (fault tolerant)

[SxN]

Never heard about bonding before, but I had a quick glance at the two links and it looks like this is what I was looking for.

Thanks,

SxN