Question About Load Balancing A Windows Server Across Two Switches

dholder · ‎01-23-2009

Good morning all,

We currently use NIC teaming software to allow our servers to connect to our two (2) server farm cores that run in active/passive mode.

We have had problems with the teaming software for years, and just recently lost of a core found several servers that the teaming software failed.

Does anyone work with their server teams that connect server NIC's to two (2) cores in a load reduancy mode? Is this possible? Our server team cannot seem to find anything.

Thanks in advance for your assistance,

Dave Holder

Giuseppe Larosa · ‎01-23-2009

Hello Dave,

to use the so called load redundancy mode you need to build an etherchannel in Cisco terminology but this means also that the two NICs need to be terminated on the same switch otherwise you will see the two switches complaining of seeing the same MAC address flapping or moving on the two ports of the two switches.

We have implemented some bundles using LACP with some success but this requires this change in design.

Hope to help

Giuseppe

john.wright · ‎01-23-2009

We have used etherchannel on a MAC server with great success. Two ports are configed like this to the same switch as Giuseppe said:

interface GigabitEthernet0/25

no logging event link-status

no snmp trap link-status

channel-protocol lacp

channel-group 1 mode active