I cannot seem to correct a duplex mismatch issue.
I have a Cisco 2950 switch connected to a Cisco 2621 router. I am running a per-interface Vlan. I have two fastethernet ports and one NM-1E card installed on the router. One fastethernet port is connected to my gateway router, the second fastethernet port is connected to my switch for one Vlan.
The NM-1E Ethernet card is being used for the second Vlan which consists of nine IP cameras.
Though the cameras on the Vlan are working fine, I am having major collision problems with the message being:
%AMDP2_FE-6-EXCESSCOLL: Ethernet1/0 TDR=0, TRC=0.
Now, the NM-1E card is set to half-duplex. I know that I should be using a fastethernet module like a 1FE 2W or a 2FE 2W card, (which I have,) but the router does not recogonize either one of these cards when they are installed, and yes, they have been confirmed as good cards.
Using Router-on-a-Stick configuration is out due to the bandwidth contention besides the fact that the router I am using it on will not handle this due to the flash being an older version.
Here is what I have done thus far to try to correct the collision issue:
I am open for suggestions at this point and have two addtional questions.
Again, I am open for suggestions at this point.
if you cannot configure duplex full under eth1/0 on the router the port is only half duplex
command accepted by the router ?
Could nine IP cameras just be too much for both the router and switch to handle?
this is the point a 10 Mbps half duplex can perform at max 3.3 Mbps in theory even less in reality. It cannot run at 10 Mbps.
Even with low resolution ( = low bit rates) nine cameras easily overcome this figure.
The best move would be IOS upgrade in order to be able to:
- support vlan subinterfaces on FE port
- and to mount an FE additional module like one of those you have and that are not recognized at the moment
Hope to help
Strange thing has occurred. I attempted to change the Ethernet port to full duplex and this time it took the command. I don't know why it didn't previously, and everything I read pointed to not being able to do this even though there was no confirmed NO to this configuration.
Once done, I forced the switchport into full duplex at the speed of 10 and now everything is GTG; all of the excessive collision messages have gone away as well.
If you cant change the interface from half duplex you have to live with collisions as this is part of a half duplex connection and is working as designed. Know that as the utilization goes up on half duplex link it will get slower and slower. Anything above 30-35% utilization on a half duplex link will make it real slow. You can't work miracles on very outdated technology .