[c-nsp] problems with etherchannel between router (3725) and switch (3550)

[Danny Vernals]

Hello all,

I'm having dificulties configuring an etherchannel (2 xFE) between a router
and switch, this is my set up:


R1
| |
Cat1
/ \
R2 R3

The channel seems fine but I can't ping from either R2 or R3 to R1 (R2 and
R3 can ping each other fine). Or from R2/R3 to R1

When you ping from R1 to either R2 or R3 (while debugging arp) you can see
the arp requests hitting R2 and R3 and replies being sent. However the
replies never get to R1.

When you ping from R2/R3 no arp requests hit R1

Cat1 has a valid cam table for all the mac addresses concerned.
Any help here would be greatly appriciated as I'm really stuck.

Here's the vaild config:


R1:
interface FastEthernet0/0
no ip address
duplex auto
speed auto
channel-group 1
end

interface FastEthernet0/1
no ip address
duplex auto
speed auto
channel-group 1
end

interface Port-channel1
ip address 195.92.202.1 <http://195.92.202.1>
255.255.255.248<http://255.255.255.248>
hold-queue 150 in
end

R2:

interface FastEthernet0/0
description CAT1 F0/4
ip address 195.92.202.6 <http://195.92.202.6>
255.255.255.248<http://255.255.255.248>
duplex auto
speed auto
end


R3:

interface FastEthernet2/0
description CAT2 F0/3
ip address 195.92.202.2 <http://195.92.202.2>
255.255.255.248<http://255.255.255.248>
duplex auto
speed auto
end

Cat1:

interface FastEthernet0/1
switchport access vlan 3
switchport mode access
channel-group 1 mode on
end


interface FastEthernet0/2
switchport mode dynamic desirable
end

interface Port-channel1
switchport access vlan 3
switchport mode access
end



Thanks in advance for your help

Danny