Multicasting between VLANs

Hi,

I'm currently configuring up our 3COM 5500G-EI Layer 3 Switch for VLANing across the school.

All the appropriate VLANs, VLAN Interfaces etc, DHCP Helper, trunk ports etc have been setup, and all the computers are connecting; allocated a correct IP address and can successfully access devices inbetween VLANs.

I just need some advice on what settings I would need to configure on the switch (all the other switches are 3COM as well) to allow multicasting across VLANs? (for Ghost, Windows Deployment).

I've come across various potential commands:

multicast routing-enabled
igmp enable
pim sm
rip version 2 multicast

On Edugeek, i've only found 1 post from last year that suggested dense mode, but this initially floods the network to find members of the multicast, whereas sparse mode doesnot.

Again, any assistance (as the 3COM, H3C, HP support forums are not very helpful on this topic!) would be very much appreciated.

Hi MYK-IT,

I believe if you wish to multi-cast between VLAN's you would need to buy like an premium\advanced license for your core, I believe this is correct for HP\Cisco (i think!).

I'm not too familiar with the 3com switches

Thanks IanT,

I'm sure the 5500G-EI can handle it though, as it has the enchanced firmware / functionality.

Even so, how do other Edugeekers who have VLAN'd their network use deployment services like Ghost, WDS, MDT etc. that rely on multicast broadcasts (for performance and not to flood the network)?

Or do you simply plug in a laptop/PC with the Ghost Server / WDS etc. software installed, into the local VLAN where you need to (re)deploy the images etc?

Thanks again,

We are also using 3com 5500G's. we got it configured this way:

multicast routing-enable <---- global command
pim <---- global command

on the vlan interfaces:

interface Vlan-interfacex
ip address xxx.xxx.xxx.xxx xxx.xxx.xxx.xxx
igmp enable
pim dm


regards
bio..

Thanks BIO,

I assume that I will have to configure every VLAN interface that I would like to support multicasting on?

MYK-IT

Quote:

---

Originally Posted by MYK-IT

Thanks BIO,

I assume that I will have to configure every VLAN interface that I would like to support multicasting on?

MYK-IT

---

yups :)

bio..

What config do you have on your edge switches? We are using v1910

Core switch is 5500g to be replaced withA5800 shortly. Do you disabled global igmp snooping on core switch and just have on VLAN interface?

Quote:

---

Originally Posted by MYK-IT

Even so, how do other Edugeekers who have VLAN'd their network use deployment services like Ghost, WDS, MDT etc. that rely on multicast broadcasts (for performance and not to flood the network)?

---

I don't, and it makes me want to cry. :( I use WDS, but it's all unicast. I can image a lab of thirty machines (100MB to the desktop, 1GB backbone) and it doesn't bog down that bad. The problem is we have dumb switches scattered all over the network so it makes multicasting impossible. When imaging parts of a lab or building I can isolate I'll bring a laptop with 2008R2 loaded onto it with WDS configured and jack it into that local network segment. Not pretty, but it works...