Multicast woes

[free780]

Does anybody have a 32 bit server acting a a deployment server. Ours is Server 2008. I'm trying to deploy a 13GB image as a pose to the 6/7GB ones in the past. Though multicast seems to fail and fallback to unicast with that image (not the default install.wim) . Is there a limit on image size when using a 32 bit server? The server is a vm on hyper v host 2008 r2 It has 2GB dynamic memory assigned. Edited July 24, 2013 by free780

[free780]

So looks like more than 1 client using multicast causes multicast to fail. Anybody had anything similar?

[sted]

its as likely to bve switch config multicast wds/mdt i just find slow and unreliable but never had time to track it down

[free780]

Well it is working at 6000kbps with a 6/7gb image on multiple computets doing multicast. So its not a switch issue unless wds is doing something as its 13gb.

[Duke5A]

I wonder if WDS attempts to cache large portions of the image in RAM when running multicast. How much RAM is in the box? File size limit for NTFS (regardless of x32 or x64) is like 16TB or something.

[strawberry]

What are the processor, ram , disk access and network connections reading like in perf manager?

[free780]

Well the CPU hits 70-90% when more than 1 client tries to multicast a 13GB image. The server has 2GB of memory assigned using dynamic memory on hyper-v. It only uses 1.2GB in task manager at time of starting multicast. However because unicast kicks in on clients it increases cpu,ram and network. Any idea of 4GB ram would improve multicast? Edited July 25, 2013 by free780

[strawberry]

Wouldnt hurt. Another processor might do the job too.

[free780]

Figured it out images above 6/7GB created in virtualbox cause the problem. When creating in hyper v a 11gb image m/casts fine. Follow Johans advice don't use virtual box for creating images use hyper v or vmware.

[free780]

Switched to 64 bit 2012. Slow multicast but is working. How long does it take 2008 r2 / 2012 to learn you network and adjust the network profile as you cant manually do it.

[free780]

Ok network port needs flow control on the host. 1gbps to 100mbps with multicast creates errors without it.

[Jamo]

Ok network port needs flow control on the host. 1gbps to 100mbps with multicast creates errors without it.

 

 

Is IGMP enabled on your switches? If not you will be broadcasting instead of Multicasting as the switches won't be able to determine the multicast membership.

[free780]

Yeah it is v3 both querier and snooping.

[free780]

OK been on this issue for 2 weeks+ . If I drop the speed to 100mbps on server (vm and host) the multicast flies. If I create a private network the performance is poor is 1gbps vm nic is used. If I switch to the legacy 100mbps for server and client it flies.

 

I can have the server with a legacy adapter for the time being but this is not a ideal solution.

 

Anybody had any similar issues and how to solve them? I can't configured flow control in the VM neither can I drop the physical port to 100mps. I can't believe no one else has has this issue. Or that using all microsoft products there is the bottle neck for 100mbps clients.

[free780]

Solved it.

 

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Providers\WDSMC\Protocol\TpMaxBandwidth

Needs to be set as 1 (decimal) restart wds. Speeds of 10000kbps with 100mps clients.

Edited October 14, 2013 by free780