NLB Problems

m4cc45 · 28 May 2009 at 10:29

Hi,

I have a really weird NLB problem. It's just a simple two node stand-alone solution - both have the same admin usernames and passwords and can see each other fine.

Node A: 10.0.0.1
Node B: 10.0.0.2
NLB: 10.0.0.10

When they are not load balanced they work fine, they can access resources and all is fine.

When they are NLB the cluster making fails yet I can see all the details under the Network card. As soon as they are configured they loose connection to each other so:

Ping 10.0.0.2 without NLB is fine
Ping 10.0.0.2 with NLB fails

Any ideas?

M.

SteffenFreund · 28 May 2009 at 11:43

Has it ever worked? and how are they connected (switch?)

katana6434 · 28 May 2009 at 20:54

Try making the NLB cluster using multicast mode instead of unicast. That solved a lot of my problems with NLB.

m4cc45 · 28 May 2009 at 22:03

Its a bit of a strange layout as they are on two physical sites connected via two switches (exactly the same config) and two firewalls.

My initial feeling is that the firewall is blocking it because NLB is like spoofing your MAC address - so that's what I'm looking into.

Tried both unicast and multicast mode to no avail.

If anyone has any other ideas in the mean time - going to interogate the logs soon.. that will be fun..

M.

McMuffin · 1 Jun 2009 at 19:45

http://support.microsoft.com/kb/898867

m4cc45 · 2 Jun 2009 at 12:53

Thanks McMuffin.

Well found the problem and it was because we have two links to the second site. Told the switch to use just the one link and it's all good.

M.