Unsolved
This post is more than 5 years old
3 Posts
0
51578
April 2nd, 2008 09:00
PC 6248 multicast configuration
Hello,
hereby i'd like to address to anyone more experienced who could provide some help on the following subject.
Namely, we have one Dell PowerConnect 6248 switch configured with different VLANs with inter VLAN routing enabled. We are trying to implement ghost multicast service in our network for those posts that need frequent ghosting (mostly classrooms with approx 20 post/classroom, each classroom is on dedicated VLAN configured on PC6248, to be more precise, for each classroom all the posts are connected to one layer 2 switch (nonadministrable and IGMP unaware) which is then directly connected to designated VLAN port on PC6248 switch). Ghost server (GSS1.1) is in separate VLAN (for servers). What we woulld like to achieve is that when the posts in one of the classrooms (meaning in one VLAN) need to be ghosted are the only ones receiving the multicast stream and that the stream doesn's flood all the network.
I would appreciate if anyone could give some precise steps on configuring PC6248 (switch and router configuration part) for this to work (if possible of course). So far attempts resulted in either very slow ghosting performance, network flodding or multicast session not starting at all.
Thanks in advance!
sentinel-master
345 Posts
0
April 4th, 2008 17:00
The classorm switch you describe as a simple layer 2 switch -what is it ?
Are you able to program MAC addrresses into it -so that you pseudo create IGMP like functionality - i.e by mapping L2 unicast addresses into a L2 mulicast address -which is derived from you L3 Class D muticast address.
If you cannot do this on the L2 switch - then you will always flood a Multicast stream to all PCs on the downstream switch - and hence interupt their CPU and have poor performance.
drunder
3 Posts
0
April 4th, 2008 23:00
Hi sentinel and thanx for the reply!
Well, the classroom switch is ZyXEL ES-1024 10/100 24 ports unmanagable switch and therefore i dont think it would be possible to apply your suggestion (unless im wrong). We managed to make ghost working someohow (even PXE boot for the classroom PCs). But what happens is when the ghostcast session is running (whether it is a multi or unicast) if some other user on a different VLAN simultaneously starts copying a file (>500MB) from a file server which is in the same VLAN as a ghostcast srv then both (gc session and file copy ) transfer rates will become terribly downgraded (time for both sessions to finish +5h). For pourpose of the test i heve tried to connect relevant machines (file server, ghostcast srv, PC to ghost, PC to copy file) directly to the Dell PC6248 ports with the same downgraded results when those two sessions are run simultaneously, if not then everything looks pretty much OK. By the way, all classroom PCs are dell optiplex with 1Gb NICs. I'm trying to figure out what could be a possibloe reason for this if not PC6248 config?
Thanx once again for the reply and cheers
drunder
PS: sorry, i know it sounds confusing but im writing this at 2 am :))
sentinel-master
345 Posts
0
April 6th, 2008 13:00
So the ZyExel 1024 is just a basic layer 2 switch- with no configuration options and multicast unaware - so for this requirement the Zyexel is not a viable part of your solution - it will always flood multicast L2 traffic sadly to all ports.
On the Powerconnect 6248 though you should be able enable "IGMP Snooping" on the PC/Server ports and hence restrict multicast traffic to "interested" - joined hosts.
When you did your ghost & file-copy test on the 6248, was IGMP Snooping enabled ?
drunder
3 Posts
0
April 6th, 2008 21:00
hi again,
"When you did your ghost & file-copy test on the 6248, was IGMP Snooping enabled ?"
- No , actually we didn't try with IGMP snooping enabled while PC/Server were connected directly to dell 6248. I'll give another try with this option enabled this time , will keep you informed what the results are.
Cheers
drunder