Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

how to supply server redundancy that supports (r)stp?

in a huge network; access switches, distribution switches and core switches are all redundant.

but I like to make redundant connection for my server too. (server has 2 ethernet ports)

which software should I install on the server?

I suppose the software should support RSTP so it can work smoothly with switches (BPDU messages, etc).

On cisco pdf's, i ve seen end user can connect to switches redundantly from two ethernet ports. but they dont explain how to achieve it?

tx for any help

Cisco Employee

Re: how to supply server redundancy that supports (r)stp?

If your server NICs support LACP, you can configure it as an LACP etherchannel to the switch, which will help you avoid having to install/purchase additional software. This way, you get both redundancy as well as additional bandwidth.




Re: how to supply server redundancy that supports (r)stp?

The LACP idea is cool, but you would than have a single point of failure since they both have to go into the same switch.

If you want to be really redundant you would want both server NIC's going into seperate switches.


New Member

Re: how to supply server redundancy that supports (r)stp?

tx for your commands.

exactly Daniel. LACP makes ethernet ports redundant but doesnt prevent single point of failure which is a nightmare.

i need two server nics to connect to two switches.(two switches are connected each other) so nics should run a mechanism similar to switches' STP so they can listen to the ports and if a port fails switchover to the other one.

i dont think this is a fantacy. there should be a solution for this.

New Member

Re: how to supply server redundancy that supports (r)stp?


You're right, it's not a fantasy.

It's usually part of the NIC driver setup.. ie the NIC vendor has to support it, and it comes with the card.

3Com, HP, IBM, Broadcom etc.. server-class nics have a similar function here. Some call it 'Teaming' and other names.

Basic concept is ..

Trunk your server vlan between the two switches

Install the required nic drivers. This typically creates a 3rd logical adapter on your OS. You configure your IP parms etc on this logical adapter.

The nics go to different switches and the drivers will determine which adapter is up/down and work accordingly.

Test this well in a lab first, as it can be tricky

Sorry, don't remember which nics are better than others here.