Multicast times out and unicast deploys the image
We have a single primary site server with 40 distribution points at 40 different locations. However, we user our primary site server as a distribution point as well for the location where the site server resides. Here is the issue. At all the other 40 different locations, when we image, Multicasting works just fine on the workstations. However, at this one location when we image from the primary site server, the workstation that is going to get imaged begins the task sequence, and displays "Waiting ## seconds for more clients to join multicast session" (I have set the time on multicast to 1 min and a minimum of 1 machine joined). The machine will count down the minute, then do the same thing a second time, and then begins unicasting the image. The primary difference I can see with this location and the 40 other locations is that at the 40 other locations, the machines, and server are on the same subnet. At the primary site location, the machines are on a different subnet from the Primary Site Server DP. Is this likely the problem? If so, is it an issue with IP Helper or something else?
October 25th, 2010 6:52pm
Do you have your network infrastructure configured to handle multicasting? The bulk of the work in multicasting is handled by the network infrastrucuture in any non-trivial (single-subnet) environment.Jason | http://myitforum.com/cs2/blogs/jsandys | http://blogs.catapultsystems.com/jsandys/default.aspx | Twitter @JasonSandys
October 25th, 2010 10:30pm
Hi, I think your problem is due to the 2 subnets isued between server and clients and maybe switchs. First of all, make sure that IGMP Snooping is enabled on all swith between your server and your clients. If IGMP Snooping isn't enabled, multicast traffic is considered as a broadcast by your switch and if your have multiple VLAN, broadcasts should be stoppped. This is the reason why the multicast stops immediattly. If it is possible, i advice you to put you DP on the same subnet as your clients. It's often simpler than asking network team to configure switchs, VLAN routers, etc :-) Have a nive Day, Régis
October 26th, 2010 2:53am