I have a 4GB XP image to deploy and I've noticed that if I deploy to 1 machine using unicast it takes around half an hour, if I deploy 1 machine via multicast (autocast)it takes around 4 hours!THe WDS server is using around 2% network utilisation during the deployment which doesn't seem like much to me.Is there anything I can do to speed up multicast deployment. I was looking at using custom network settings in the multicast settings within SCCM but I cannot find details of what each reg value actually does.Any help would be appreciated!Cheers

have you looked at this post about the same thing, there are some registry settings which can be tweaked as the gui settings relating to multicast sometimes get ignored.... http://social.technet.microsoft.com/Forums/en-US/configmgrosd/thread/35e948c7-7fb1-45c6-99c9-999f365d9221 My SCCM Guides http://www.windows-noob.com/forums/index.php?showforum=44

Hi Niall, Yes, it explains that the registry can be updated and the key to update, but doesn't go into what the values actually do. They seem very similar between the 100Mb and 1Gb settings other than the cache size.

dont bother changing the profile values themselves but change the actual profile that is chosen (on my sccm server the default is 100Mbs in the registry), please read this post as well, in particular this part I also tried changing the Transfer Rate (10Mbs, 100Mbs, 1Gbs, Custom) and those never got updated in the registry either. The only way I found to change the settings is to manually change them in the registry and restart the WDS service. The registry key to change the multicast address range is here: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Parameters] and the reg key to change the Transfer Rate is here: [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Providers\WDSMC] "DefaultProfile"="1Gbps". from > http://www.myitforum.com/forums/m_192210/mpage_1/key_/tm.htm#192210My SCCM Guides http://www.windows-noob.com/forums/index.php?showforum=44

I've checked that out Niall and made some changes in the registry to increase the profile to 1Gbps. The multicast speed is still excruciatingly slow. To test I used a smaller image (500mb) to image 2 laptops. The file download on the multicast (autocast) was 1 hour, on unicast (together) they took 4 minutes. I know that this will slow down as I add more clients but there how can the multicast be this much slower?

did you restart the Windows Deployment Services service ?My SCCM Guides http://www.windows-noob.com/forums/index.php?showforum=44

Yes, it's picked up the change.

ok and it's still slow ? did you change the multicast ip range at all ? do you have any switches in your environment which could be impacting the speed ?????My SCCM Guides http://www.windows-noob.com/forums/index.php?showforum=44

Yes, I changed the IP range to use 224.1.1.0/24 as discussed in the link you suggested earlier (no impact). During testing I actually plugged the clients into the same switch as the servers in my test environment so the network should not be a barrier.

you didnt say what switch you are using, perhaps it might be an idea to read this for some ideas ? http://supportwiki.cisco.com/ViewWiki/index.php/Slow_performance_of_LAN_due_to_a_high_degree_of_multicast_traffic_or_frequent_disruption_of_multicast_streams_and_how_to_filter_multicast_traffic My SCCM Guides http://www.windows-noob.com/forums/index.php?showforum=44

I've been having this same problem and still no resolution. (Multicast works, but very slow with only 1%-2% utilization on gigabit links) Trying different switches (cisco/enterasys gigabit managed) has no effect. Tweaking registry settings for WDS (so that they are *all* set to gigabit even) doesn't work. Tweaking the multicast registry settings specific to configmgr does not work either. (I've also tried quite a few MC IP ranges.. no difference) Reinstalling multicast point, reinstalling WDS, restarting them, etc and any reasonable permutation of those steps also does not work. Since being held up by the same issue I've found only a few people with this problem on the net. The usual answer is for someone to point you to the registry tweaks, but as I mentioned (for me and a few others atleast) this does not help. Has anyone else seen this before? Found a fix or still stuck with slow multicast? Any ideas?

This problem is very interesting so i've been doing some reading, and i'm wondering if you guys have read the Network Considerations for Multicast yet, so is the below true in your multicast environment ? Best practice recommends that the same distribution point is not used both for multicast and for unicast distributions in network environments that are likely to have high volumes of operating system deployment. For this reason, operating system deployment driver packages and non-multicast operating system images should be located on distribution points other than the multicast-enabled distribution point. My SCCM Guides http://www.windows-noob.com/forums/index.php?showforum=44

The switch has been looked at and multicast should run fine, it's been proven during a test with Ghost. I'll move these images to another DP and try again.

Regarding Brady's point.. I don't think that this is causing my hold up. When I test my multicast runs I can guarantee that nothing else is hitting the server. Besides, I can unicast tons of boxes simultaneously, but running just a single multicast client is just as slow as running 10. :/ It is a good point however on a very busy DP.

I'll also try adding a new DP for MC testing only and see what happens. :)

I still can't figure out what registry setting needs to be applied for the transfer rate setting... I have [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WDSServer\Providers\WDSMC] with a string value of "DefaultProfile"="1Gbps". Is that what/where this is needed? Or is the DefaultProfile supposed to be a reg key and there are different values in that key? With the above setting, I am still seeing 2mbps on our 100mb nic. I know 1gbps is more than what our 100mb nic can handle, but I have also tried 100mbps and had the same result. TIA

The key listed on the Microsoft page and the SCCM help documentation doesn't evenexist. Transfer Rate Specifies the transfer rate of the network used for multicast. Each rate enables settings to optimize performance for the specified speed, such as the maximum transport window size, the transport cache size, and the block size. Select Custom if you want to customize the settings by editing the registry. Even if you want to change only one setting, you should create a custom profile by first copying the needed profile into the custom profile. Registry settings can be viewed at HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services \ WDSServer \ Providers \ Multicast \ Profiles. Do not modify the other profiles that are provided. I get down to "Providers" but there is not a "Multicast" folder after that? What is that about? Find this post helpful? Does this post answer your question? Be sure to mark it appropriately to help others find answers to their searches.