04-10-2003 09:42 PM - edited 03-02-2019 06:35 AM
First of all, thanks to whoever suggested the keepalive fix for someone else.
I have a pair 7513 routers connected to a pair 2924M switches with 2922 100BaseFX fibre connections. I have set them up as a fastetherchannel pair and run ISL on top of that. Then I got HSRP on top of the trunks with another router. One router talks to each switch.
I used to get lots of received CRC errors on the switches on both ports that listen to the router (every 10 seconds). Turning keepalives off the routers 100BaseFX interfaces almost fixed it. I now get a CRC error every 60 seconds.
So its not keepalives, but it has to be something else like that, what could it be that has a 60 second interval and messes up fasttherchannel?
I get no CRC errors anywhere else, including another fastethernet channel that links the two routers, and the interface on the routers that listen to the switches so its not length problems. The length of the fibres is about 100/200 meters between the router and switch and 300 meters between routers.
router1 -- 200m -- switch1|switch2 -- 100m -- router2
04-11-2003 08:09 AM
Turn off trunk negotiation on the switch trunk ports and force trunking on. I think it is DTP packets causing the errors. I could be wrong. Let me know either way.
04-13-2003 07:34 PM
Already have trunking turned on on the switch.
This is its configuration
interface FastEthernet1/1
port group 2
switchport mode trunk
And this is the router, I have cut and pasted the three level configs, the interface, the port-channel and the vlan on the port-channel
If it is the DTP packets, perhaps it is the router doing something?
The "no keepalive" was recently added after reading a previous message.
interface FastEthernet1/1/0
no ip address
no keepalive
full-duplex
channel-group 2
!
interface Port-channel2
no ip address
ip ospf message-digest-key 20 md5 7 somethinghere
full-duplex
hold-queue 300 in
!
interface Port-channel2.10
encapsulation isl 10
ip address 10.1.2.3 255.255.255.240
no ip redirects
ip ospf cost 2
standby 2 ip 10.1.2.1
standby 2 priority 50
standby 2 preempt
standby 2 authentication something
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