Servers with Dual NICs for redundancy, should I use both?

[Shuka]

Hey,

I have 5 rackmount servers, each of which have 2 NICs for redundancy. The rack has a 12-port switch. My problem is if I connect both NICs from each server to the switch, I will only have 2 remaining ports to work with. How often does a NIC die? How would this happen? The servers and switch are hooked up to surge protectors and UPSs so power surges shorting out the NICs shouldn’t be a problem. Does the advantage of having NIC redundancy outweigh the hassle of using up ports and possibly having to add another switch?

Thanks for any help.

 

[alrox]

You don't get any real redundancy with 2 NIC's on the same switch. NIC's have a high MTBF, probably higher than the switch they're plugged into. NIC redundancy is more helpful when each NIC is plugged into a different switch so that in case either the main NIC or switch fails, the secondary NIC goes into action.

 

[Anthony.L]

As alrox pointed out two NIC connections into a single switch isn't a good design. You still have a single point of failure, the switch.

I would get a second switch and connect one NIC in each server to a seperate switch. Then on the server configure "NIC teaming" which handles the redundancy. When one NIC dies the other NIC should automatically come online with the same IP and MAC address as the dead NIC. Thus very little down time. Now this could all be overkill depending on what the servers do. But that's up you to decide.