[c-nsp] Microsoft multicasted cluster vs. Cisco IOS

Tue Nov 8 04:22:29 EST 2005

Thanks for that. But are you saying then that the MSCS heartbeat, which MS 
claims is unicast for two servers or for all servers
if they're running heterogenous OSes and multicast for three or more 
homogenous OSes can't be routed and definitely
requires the private vlan?

Internet
brian at briandesmond.com
07/11/2005 19:09

To
Christian MACNEVIN, olivier.dauby
cc
cisco-nsp
Subject
RE: [c-nsp] Microsoft multicasted cluster vs. Cisco IOS

That is correct:

MSCS - Microsoft Cluster Services
This is their failover solution - you have multiple hosts connected to
shared storage (SAN) running something like Exchange or SQL. The hosts
exchange heartbeats over a private vlan (they can have up to 500ms of
latency before it stops working). There is a public network the clients 
talk
to the cluster on, and then the application resources, storage, etc. The
cluster resource for the application and the resources built into MSCS
monitor to make sure everything is hunky dory and if not a failover 
happens

NLBS - Network Load Balancing Services
This is MS' software LB service. It's designed for load-balancing scaled 
out
servers, e.g. a webfarm that talks to a backend database cluster. It works
fine, but, sometimes getting it setup can be a real PITA when it doesn't
play right with the network.

The bit in that technote *does not* apply to MSCS - Cluster Services, just
NLBS - Network Load Balancing. MSCS doesn't support active/active in the
sense of a load balancing solution, so it doesn't do this stuff with the
multicast MACs.

Despite what MS claims on that page, I discovered that at least with the
Compaq NIC drivers, teaming doesn't work well with NLB. NLB will fiddle 
with
the MACs on some of the parts of the team but never all and then things 
end
up breaking.

Thanks,
Brian Desmond
brian at briandesmond.com

c - 312.731.3132

-----Original Message-----
From: cisco-nsp-bounces at puck.nether.net
[mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of
christian.macnevin at uk.bnpparibas.com
Sent: Monday, November 07, 2005 4:37 AM
To: olivier.dauby at scarlet.be
Cc: cisco-nsp-bounces at puck.nether.net; cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] Microsoft multicasted cluster vs. Cisco IOS

I'm told by someone who purports to know a bit about Microsoft that
microsoft clustering service != Network Load Balancing. Don't
ask me, I just poke the routers.

The tech note seems to be specific to NLB. So does it hold true for both
services? Anyone?

Cheers
Christian

Internet
olivier.dauby at scarlet.be
Sent by: cisco-nsp-bounces at puck.nether.net
04/11/2005 17:11

To
cisco-nsp
cc

Subject
Re: [c-nsp] Microsoft multicasted cluster vs. Cisco IOS

Brett Looney wrote:
> At 00:44 5/11/2005, you wrote:
>
>>The Microsoft cluster is supposed to listen on a virtual ip address
>>using a multicast mac address. Local users see the virtual ip of the
>>cluster (10.106.49.6) with a mac address 03:BF:0A:6A:31:06. I'm
>>already a bit confused here since I expected the multicast mac
>>address to begin with 0x01 instead of 0x03.
>>
>>The routers also seem to be confused, they have been unable to learn
>>this mac address as you can see in this 'show arp' output:
>>
>>I quickfixed this with a dirty 'arp' command on both routers:
>>
>>        arp 10.106.49.6 03BF.0A6A.3106 arpa
>
>
> Yeah - there is a MS technote about this (can't find it right
> now...). Routers won't learn a multicast MAC address for a unicast IP
> address. You've done exactly what they suggest...
>
> B.

Oh I see,

http://www.microsoft.com/technet/prodtechnol/windowsserver2003/library/Serve

rHelp/fdcd461f-0fd6-4164-928f-6f1841fdc27d.mspx

Thanks for your support,

O.

_______________________________________________
cisco-nsp mailing list  cisco-nsp at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/

This message and any attachments (the "message") is
intended solely for the addressees and is confidential.
If you receive this message in error, please delete it and
immediately notify the sender. Any use not in accord with
its purpose, any dissemination or disclosure, either whole
or partial, is prohibited except formal approval. The internet
can not guarantee the integrity of this message.
BNP PARIBAS (and its subsidiaries) shall (will) not
therefore be liable for the message if modified.

****************************************************************************
******************

BNP Paribas Private Bank London Branch is authorised
by CECEI & AMF and is regulated by the Financial Services
Authority for the conduct of its investment business in
the United Kingdom.

BNP Paribas Securities Services London Branch is authorised
by CECEI & AMF and is regulated by the Financial Services
Authority for the conduct of its investment business in
the United Kingdom.

BNP Paribas Fund Services UK Limited is authorised and
regulated by the Financial Services Authority

_______________________________________________
cisco-nsp mailing list  cisco-nsp at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/