RE: [load balancing] Cluster Heartbeat Redundancy on IBM Blade Servers

From: Seth Kusiak <SKusiak [izzat]>
Date: Sun Oct 08 2006 - 22:08:48 EDT


You can accomplish what you're looking to do within MSCS itself. In
MSCS, you can configure your NIC's in three modes: 1) Private only, 2)
Public only, and 3) Mixed communication. You can keep your upper NICs
dedicated as the private heartbeat network then configure your lower
NICs in Mixed communication mode within MSCS. You'll want to assign your
upper NICs a higher priority so that heartbeat traffic will always flow
on that private network unless that connection goes down. Heartbeat
traffic will then flow through your production network.

The solution above is the preferred method, but here are some other

1) Take the Nortel out of the mix by connecting a cross over cable
between the two servers. I'm assuming you have a two node cluster here.
2) Implement VLANs on your NICs. This assumes that your NICs (and
the Nortel) support VLANs.



-----Original Message-----
From: [] On Behalf Of
Sent: Wednesday, October 04, 2006 2:38 AM
Subject: [load balancing] Cluster Heartbeat Redundancy on IBM Blade

Hi Everyone,

I have implemented Microsoft SQL Clustering on 2 IBM Blades, i have used
the upper NIC's for the heartbeat which uses a private IP and the lower
NIC's as the production IP's, during System Acceptance Testing, pulling
out either blade automatically transfers cluster resources to the other,
thus successfully implementing cluster fail-over. The problem arises
when the upper Nortel L2-L7 switch was pulled out from the setup,
heartbeat of the cluster failed to identify which blade failed,
Microsoft suggets that i should provide redundancy on the heartbeat by,
having multiple NIC's for heartbeat, problem is, blades only have upper
and lower nics, on my setup i have alraedy used the lower nics as the
public IP to access the resources, how could i configure the switch and
the blades to handle multiple IP's per NIC where one IP set is for
public use (i.e. resource access) and the other set defined on the same
NIC is for private use (i.e. heartbeat) so as to accomplish full
redundancy on blades and on switches for public and private network,
hope anybody there could help me out on this, thanks a lot in advance!

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Received on Sun Oct 8 22:08:53 2006

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