We are having a performance issue with ZENworks multicast. The problems occurs when the imaging server is connected with 1 Gbit and the clients are running 100 Mbit. The multicast session is extremely slow. It performs like 10 Mbit (12 GB image takes 6-7 hours)

If we change the imaging server's nic to 100 Mbit the multicast session performs OK (12 GB image takes ~50 min.)
We also did another test: server 1 Gbit and clients 1 Gbit. This also performs OK.

There is nothing wrong in our network environment. We can run Ghost multicast server with server nic set to 1 Gbit and clients set to 100 Mbit (same client machines as with ZCM multicast). This performs OK.

We have tested this with both Windows and Linux ZCM backend imaging servers. Currently we are running ZCM 10.3 but we have also seen this on 10.2.2.

Is there a setting (/etc/opt/novell/zenworks/preboot/novell-zmgmcast.conf) that I missed or is it a bug in ZCM multicast? Also seen this issue discussed in other threads, but never found a solution.