I have got 2 switches facing to each other through an L3 etherchannel:
SW4(config-if)#do sh ip eigrp nei
EIGRP-IPv4 Neighbors for AS(10)
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 155.1.108.8 Po1 10 02:57:52 1 200 0 66
SW2(config-if)#do sh ip eig nei
EIGRP-IPv4:(10) neighbors for process 10
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
1 155.1.58.5 Vl58 11 02:36:13 9 200 0 72
0 155.1.108.10 Po1 12 02:58:52 1 200 0 36
The port channel is woking fine:
on SW2:
Number of channel-groups in use: 1
Number of aggregators: 1
Group Port-channel Protocol Ports
------+-------------+-----------+-----------------------------------------------
1 Po1(RU) - Fa0/19(P) Fa0/20(P)
and on SW4:
Number of channel-groups in use: 1
Number of aggregators: 1
Group Port-channel Protocol Ports
------+-------------+-----------+-----------------------------------------------
1 Po1(RU) - Fa0/16(P) Fa0/17(P)
SW2 receives eigrp external routes from Vlan 58:
SW2(config-if)#do sh ip route | i EX
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
D EX 204.12.1.0/24 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 4.4.1.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 4.4.2.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 4.4.3.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 31.3.0.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 31.2.0.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 31.1.0.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 31.0.0.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 30.2.0.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 30.3.0.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 30.0.0.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
D EX 30.1.0.0 [170/2560512512] via 155.1.58.5, 01:20:02, Vlan58
This routing table matches what's in the eigrp topology:
SW2(config-if)#do sh ip eig top
EIGRP-IPv4 Topology Table for AS(10)/ID(150.1.8.8)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 155.1.5.0/24, 1 successors, FD is 28416
via 155.1.58.5 (28416/28160), Vlan58
P 155.1.13.3/32, 1 successors, FD is 2682112
via 155.1.58.5 (2682112/2681856), Vlan58
P 155.1.45.0/24, 1 successors, FD is 2170112
via 155.1.58.5 (2170112/2169856), Vlan58
P 150.1.8.0/24, 1 successors, FD is 128256
via Connected, Loopback0
P 30.3.0.0/16, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 150.1.10.0/24, 1 successors, FD is 143360
via 155.1.108.10 (143360/128256), Port-channel1
P 155.1.23.0/24, 1 successors, FD is 2682112
via 155.1.58.5 (2682112/2681856), Vlan58
P 30.1.0.0/16, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 155.1.108.0/24, 1 successors, FD is 15360
via Connected, Port-channel1
P 4.4.2.0/24, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 31.0.0.0/16, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 31.3.0.0/16, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 150.1.2.0/24, 1 successors, FD is 2298112
via 155.1.58.5 (2298112/2297856), Vlan58
P 30.0.0.0/16, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 204.12.1.0/24, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 150.1.5.0/24, 1 successors, FD is 130816
via 155.1.58.5 (130816/128256), Vlan58
P 155.1.13.1/32, 1 successors, FD is 21024256
via 155.1.58.5 (21024256/21024000), Vlan58
P 155.1.8.0/24, 1 successors, FD is 2816
via Connected, Vlan8
P 155.1.23.2/32, 1 successors, FD is 21024256
via 155.1.58.5 (21024256/21024000), Vlan58
P 31.2.0.0/16, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 192.10.1.0/24, 1 successors, FD is 2172672
via 155.1.58.5 (2172672/2172416), Vlan58
P 155.1.10.0/24, 1 successors, FD is 15616
via 155.1.108.10 (15616/2816), Port-channel1
P 31.1.0.0/16, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 155.1.58.0/24, 1 successors, FD is 2816
via Connected, Vlan58
P 155.1.23.3/32, 1 successors, FD is 2682112
via 155.1.58.5 (2682112/2681856), Vlan58
P 155.1.45.4/32, 1 successors, FD is 2170112
via 155.1.58.5 (2170112/2169856), Vlan58
P 4.4.1.0/24, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 155.1.0.0/24, 1 successors, FD is 2170112
via 155.1.58.5 (2170112/2169856), Vlan58
P 155.1.13.0/24, 1 successors, FD is 2682112
via 155.1.58.5 (2682112/2681856), Vlan58
P 4.4.3.0/24, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
P 30.2.0.0/16, 1 successors, FD is 2560512512
via 155.1.58.5 (2560512512/2560512256), Vlan58
but external routes are not advertised to SW4:
SW4(config-if)#do sh ip route | i EX
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
Neither they are in the topology:
SW4(config-if)#do sh ip eigr topolo
EIGRP-IPv4 Topology Table for AS(10)/ID(150.1.4.4)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 155.1.5.0/24, 1 successors, FD is 30976
via 155.1.108.8 (30976/28416), Port-channel1
P 155.1.13.3/32, 1 successors, FD is 2684672
via 155.1.108.8 (2684672/2682112), Port-channel1
P 155.1.45.0/24, 1 successors, FD is 2172672
via 155.1.108.8 (2172672/2170112), Port-channel1
P 150.1.8.0/24, 1 successors, FD is 143360
via 155.1.108.8 (143360/128256), Port-channel1
P 150.1.10.0/24, 1 successors, FD is 128256
via Connected, Loopback0
P 155.1.23.0/24, 1 successors, FD is 2684672
via 155.1.108.8 (2684672/2682112), Port-channel1
P 155.1.108.0/24, 1 successors, FD is 15360
via Connected, Port-channel1
P 150.1.2.0/24, 1 successors, FD is 2300672
via 155.1.108.8 (2300672/2298112), Port-channel1
P 150.1.5.0/24, 1 successors, FD is 143616
via 155.1.108.8 (143616/130816), Port-channel1
P 155.1.13.1/32, 1 successors, FD is 21026816
via 155.1.108.8 (21026816/21024256), Port-channel1
P 155.1.8.0/24, 1 successors, FD is 15616
via 155.1.108.8 (15616/2816), Port-channel1
P 155.1.23.2/32, 1 successors, FD is 21026816
via 155.1.108.8 (21026816/21024256), Port-channel1
P 192.10.1.0/24, 1 successors, FD is 2175232
via 155.1.108.8 (2175232/2172672), Port-channel1
P 155.1.10.0/24, 1 successors, FD is 2816
via Connected, Vlan10
P 155.1.58.0/24, 1 successors, FD is 15616
via 155.1.108.8 (15616/2816), Port-channel1
P 155.1.23.3/32, 1 successors, FD is 2684672
via 155.1.108.8 (2684672/2682112), Port-channel1
P 155.1.45.4/32, 1 successors, FD is 2172672
via 155.1.108.8 (2172672/2170112), Port-channel1
P 155.1.0.0/24, 1 successors, FD is 2172672
via 155.1.108.8 (2172672/2170112), Port-channel1
P 155.1.13.0/24, 1 successors, FD is 2684672
via 155.1.108.8 (2684672/2682112), Port-channel1
I removed Po1 and used a simple routed switchport instead (sw2-fa0/21 facing sw4-fa0/18), but the problem remains. I do not understand why. Furthermore, I have already used the same architecture and it was fine, all the external were advertised on SW4, but after quite a long time.
