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Cisco 3750 Ghost Multicast Issues

jlamphere
Level 1
Level 1

We are having problems with Symantec Ghost 8.0 (Solution Suite 1.0) multicast sessions autonegotiating and transmitting at 10MB half duplex over stacked 10/100 Catalyst 3750s (WS-C3750-48PS-E). Both sides of the connection are set to autonegotiate. The clients will connect at 100MB full duplex and start the multicast session but then we will immediately see one port on the 3750 drop to 10MB half duplex and log thousands of collisions. If we kill the session and drop that system out of the mulicast and retransmit, then another port will automatically drop to 10MB half duplex as soon as the data starts to push. We use the same NIC chipset and NDIS drivers for Ghost throughout our entire operation but are only having this problem with two switches in the stack (7 total). If this were an overall incompatibility issue between the NDIS driver we're using (Broadcom 57xx), ghost, and the Cisco IOS then why do we not see this behavior on all of our switches? Our operation is too large (university) to hard code 100MB full duplex on both sides of the connection so we really need autonegotiation to work. We do not see any collisions on these switches when we are not using Ghost multicast. CPU and memory utilization on the 3750s are normal while the session is transmitting. We've tried the suggested fixes from Symantec (which really only included messing arround with TTL values on the ghost server end) and different versions of NIC drivers to no avail.

5 Replies 5

Roberto Salazar
Level 8
Level 8

Can you check if IGMP-snooping is working? make sure that the mcast traffic is not being flooded. It sounds strange when you start pushing mcast traffic another port is affected. Is the port negotiating down to 10/half the same port where the mcast stream is being rx by the client?

There are multiple clients receiving the mcast stream and each time a different client/port has the problem. All it takes is one port throttling down to slow the ghost multicast for the entire session (effectively a 15GB image which should take 40min to ghost at 100MB full duplex takes 4.5 hours to complete). IGMP snooping is working as far as I can tell. We're not seeing any multicast or broadcast packet floods during the ghost session and I'm seeing the IGMP, CGMP, and PIMv2 communications happening between the switches and routers via packet sniffs. We aren't doing any deliberate bandwidth throttling at all (QoS not enabled).

We've circumvented the Cisco switches in question with several different portable switches from other manufacturers and can image out fine at 100MB full duplex. As I stated in my original post, we can also ghost through other 3750s in the same stack with no problem. I also have two other floors in our building that use stacked Catalsyst 3750s and we have no issues with them as well.

We're not getting any packet loss or corruption. Just reduced throughput.

pciaccio
Level 4
Level 4

My experience with Ghost Ver 8 is that the server is hard coded for 100/full. All the clients have to be coded autonegotiate. That works fine. All my machines come up at 100/full and I can get about 300-400mbps throughput to all machines. I know that you need to get the latest in NIC drivers...Hope this helps..Good Luck..Please rate...

The clients and switches are all coded to autonegotiate by default and they do until the push starts. As soon as data hits the wire we'll have one port immediately drop to 10MB half duplex. It doesn't matter how many client we have in the job ... if the multicast session traverses these particular switches in the stack we experience the problem. We've tried NIC drivers going back 6 months and still can't get it resolved.

pciaccio
Level 4
Level 4

I need to ask you, When you start your sessions you go around to all the clients and install the boot disks. Are you actually viewing the speed and duplex on these machines and confirming that they are 100/full. Maybe one or two machines are coming up at 10/half not known to you at the time..Also you state that the sessions are started, are they actually started or waiting for all the clients to register with the server. Possibly the session never takes off but is still in the process of setting up.. Just for the fun of it, have you tried to force the clients to 100/full to see what happens?? Finally you can set the Ghost logging feature on and see what is happening to the sessions. This file can be large but it is a place to start. Possibly this file can tell you more about the sessions....Good Luck..

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