NLB causing switch flooding

Hi all
We have two Server 2003 terminal servers setup with NLB (multicast)
We have tried setting this to unicast also.
The problems we are getting is that as soon as we initiate the NLB we start
to get a HUGE amount of activity on the switches often leading to them
locking up.
The NICs are also setup in teaming, but we have tried taking teaming off and
running a single NIC, we have tried various driver and firmware updates for
the NIC's, however, we do not see this issue until the NLB is put on.

Any clues as to how we get around this would be greatly appreciated

TIA

Terry

Couple of methods:

1. Put those 2 servers in their own vlan. Easy to get right.

Harder methods:
2. Unicast: Add static entries in the switches' mac/port (aka
port-forwarding database, aka CAM) tables. Tell it the Unicast address is
on 2 ports.
3. Multicast: Same as unicast, but might also need static ARP entries on
routers on same subnet as your 2 servers.
4. Multicast with IGMP. Either enable IGMP snooping, or if that doesn't
work then do as per multicast.

The mac address to use is the one shown in the NLB Administrator cluster
properties.


C.


"Terry" <> wrote in message
news:eyQjMR%...
> Hi all
> We have two Server 2003 terminal servers setup with NLB (multicast)
> We have tried setting this to unicast also.
> The problems we are getting is that as soon as we initiate the NLB we
> start to get a HUGE amount of activity on the switches often leading to
> them locking up.
> The NICs are also setup in teaming, but we have tried taking teaming off
> and running a single NIC, we have tried various driver and firmware
> updates for the NIC's, however, we do not see this issue until the NLB is
> put on.
>
> Any clues as to how we get around this would be greatly appreciated
>
> TIA
>
> Terry

"Terry" <> wrote in message
news:eyQjMR%...
> Hi all
> We have two Server 2003 terminal servers setup with NLB (multicast)
> We have tried setting this to unicast also.
> The problems we are getting is that as soon as we initiate the NLB we
> start to get a HUGE amount of activity on the switches often leading to
> them locking up.

Right, this is expected behaviour. See the following link for more info:

http://msmvps.com/blogs/clusterhelp/...b-21-2005.aspx

> The NICs are also setup in teaming, but we have tried taking teaming off
> and running a single NIC, we have tried various driver and firmware
> updates for the NIC's, however, we do not see this issue until the NLB is
> put on.

Teamingn of NLB'd NICs is probably not a good idea. See the following link
for more information:

"Terry" <> wrote in message
news:eyQjMR%...

> The NICs are also setup in teaming, but we have tried taking teaming off
> and running a single NIC, we have tried various driver and firmware
> updates for the NIC's, however, we do not see this issue until the NLB is
> put on.

Sorry, I hit the send button too fast. For more info on NLB and NIC teaming,
you can read this post:

http://msmvps.com/blogs/clusterhelp/...c-teaming.aspx


--
Russ Kaufmann,
MVP, MCSE: Messaging and Security, MCT, MCITP, MCTS and other stuff

ClusterHelp.com, a Microsoft Certified Gold Partner
Web http://www.clusterhelp.com
Blog http://msmvps.com/clusterhelp

Hi Chalky,

Thanks for your reply. Is there an easy setup guide for creating the
vlan....my understanding is that these should be on their own dedicated
switch??
I am not sure I understand how the traffic will pass from the PDC to the
load balanced TS servers and vice versa.

If we put a NIC on each TS into a VLAN and enable NLB how do we get this to
talk to the Session Directory Services on the PDC?
Also how will this affect the data traffic to the other servers and the
clients trying to connect to the TS Servers.

TIA

Terry



"Chalky" <> wrote in message
news:OQ7I$...
> Couple of methods:
>
> 1. Put those 2 servers in their own vlan. Easy to get right.
>
> Harder methods:
> 2. Unicast: Add static entries in the switches' mac/port (aka
> port-forwarding database, aka CAM) tables. Tell it the Unicast address is
> on 2 ports.
> 3. Multicast: Same as unicast, but might also need static ARP entries on
> routers on same subnet as your 2 servers.
> 4. Multicast with IGMP. Either enable IGMP snooping, or if that doesn't
> work then do as per multicast.
>
> The mac address to use is the one shown in the NLB Administrator cluster
> properties.
>
>
> C.
>
>
> "Terry" <> wrote in message
> news:eyQjMR%...
>> Hi all
>> We have two Server 2003 terminal servers setup with NLB (multicast)
>> We have tried setting this to unicast also.
>> The problems we are getting is that as soon as we initiate the NLB we
>> start to get a HUGE amount of activity on the switches often leading to
>> them locking up.
>> The NICs are also setup in teaming, but we have tried taking teaming off
>> and running a single NIC, we have tried various driver and firmware
>> updates for the NIC's, however, we do not see this issue until the NLB is
>> put on.
>>
>> Any clues as to how we get around this would be greatly appreciated
>>
>> TIA
>>
>> Terry
>
>