Hi,
I have a 3640 ("router1") with IOS v11.2 which is routing between IP subnets
(class "c" with a one bit subnet mask - using "IP subnet-zero"). There are
two Ethernet ports on the router, each is connected to a separate Catalyst
3500 XL switch. The two switch ports are hard set to 10 MBS, duplex
autonegotiate, spanning-tree on, portfast on. I am seeing collisions and
crc errors on the switch ports that are connected to "router1". The
remainder of the switch ports ( with the exception of a few ports which I'll
explain shortly ) are connected to 100 MBS fastethernet desktops and don't
show any collisions...I understand why.
I also have another 3640 ("router2") connected to the same switches, in the
same manner...for redundancy, I'm told. There are a couple of other 3500 XL
switches cascaded from these...to accommodate the number users. The LAN
size is about 125 nodes with about equal number of nodes connected to each
subnet. I'm new here...I have recommended getting rid of the subnetting
scheme in favor of a classful LAN. Anyway, the switch ports that are
connected to "router2" don't show any collisions/crc errors.
This all started 2 weeks ago. The network has been designed this way for
about a year.
In short, I can't determine whether routing loops are causing the collisions
(and if so, why only on "router1"), or whether there's a port configuration
mismatch between "router1"s Ethernet ports and the switch. Or, maybe some
piece of hardware has just failed? Any suggestions are welcome.
Jim McDowell
Cisco Certified Network Professional
Network Administrator
Copley Information Systems
858.729.8028
_________________________________
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]