I've got 2 stacks of Catalyst 4506-E switches (Core01 & Core02) with a 4 link port channel (Po1) configured between them. I've got 2 routers, a 3845 and a 7206VXR connected to both Core01 & Core02 at ports Gi4/45 and Gi2/11 on both switches. A quick diagram:
While trying to chase down a different(?) issue, I noticed in the output of show logging from Core01 and Core02 was:
Oct 19 15:16:24.807: %C4K_EBM-4-HOSTFLAPPING: Host 00:25:84:EA:60:80
in vlan 999 is moving from port Gi4/45 to port Po1 Oct 19
15:16:24.807: %C4K_EBM-4-HOSTFLAPPING: Host 00:25:84:EA:60:80 in vlan
999 is moving from port Po1 to port Gi4/45 Oct 19 15:16:34.188:
%C4K_EBM-4-HOSTFLAPPING: Host 00:22:0D:92:B0:1B in vlan 999 is moving
from port Gi2/11 to port Po1 Oct 19 15:16:34.236:
%C4K_EBM-4-HOSTFLAPPING: Host 00:22:0D:92:B0:1B in vlan 999 is moving
from port Po1 to port Gi2/11 Oct 19 15:16:35.080:
%C4K_EBM-4-HOSTFLAPPING: Host 00:25:84:EA:60:80 in vlan 999 is moving
from port Gi4/45 to port Po1 Oct 19 15:16:35.128:
%C4K_EBM-4-HOSTFLAPPING: Host 00:25:84:EA:60:80 in vlan 999 is moving
from port Po1 to port Gi4/45 Oct 19 15:16:44.189:
%C4K_EBM-4-HOSTFLAPPING: Host 00:22:0D:92:B0:1B in vlan 999 is moving
from port Gi2/11 to port Po1 Oct 19 15:16:44.189:
%C4K_EBM-4-HOSTFLAPPING: Host 00:22:0D:92:B0:1B in vlan 999 is moving
from port Po1 to port Gi2/11 Oct 19 15:16:45.081:
%C4K_EBM-4-HOSTFLAPPING: Host 00:25:84:EA:60:80 in vlan 999 is moving
from port Gi4/45 to port Po1 Oct 19 15:16:45.125:
%C4K_EBM-4-HOSTFLAPPING: Host 00:25:84:EA:60:80 in vlan 999 is moving
from port Po1 to port Gi4/45
Over and over again. Those 2 MAC addresses,00:25:84:EA:60:80 & 00:22:0D:92:B0:1B correspond to BVI1 on the 3845 and the 7206VXR, respectively.
Output of sh vlan id 999:
VLAN Name Status Ports
---- -------------------------------- --------- ------------------------------- 999 Core active Gi1/3, Gi1/4, Gi2/11, Gi2/25, Gi2/31, Gi3/18, Gi3/20,
Gi3/22, Gi3/24, Gi3/26, Gi3/28
Gi3/32, Gi4/4, Gi4/7, Gi4/11, Gi4/15, Gi4/27, Gi4/45, Gi5/2, Gi5/3, Gi5/4, Gi5/5
Gi5/10, Gi5/25, Gi5/26, Gi5/27, Gi5/28, Gi5/34, Gi5/36, Po1
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode
Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------ 999 enet 100999 1500 - - - - - 0 0
Remote SPAN VLAN
---------------- Disabled
Primary Secondary Type Ports
------- --------- ----------------- ------------------------------------------
So, port channel Po1 is in vlan 999, as are Gi2/11 and Gi4/45, Which I'm assuming is a problem, and is causing these messages. My question is this; I inherited this setup, I didn't build it,but I also haven't changed it. I've built a Debian Rancid server thats handling configuration diffs, so if this was something that was new, I'd have gotten an email about it. I admit I haven't gone back and looked at every config diff I've received in the past year, but I went back far enough to know this isn't a new change, I can assume it has been doing this for a while now. However, I see that message, I think loop.
Is it incorrect to have Po1 and the interfaces that are connected to the routers in the same vlan? Also, those ports are access ports, should I not trunk them? Any ideas would be appreciated.
Thanks,