problems getting vpc peerlink up on nx 5000

tiwang · ‎10-08-2011

hi out there

I am trying to get a vpc betweeen 2 sets of nexus running 5.0.(3)N2(1)up and run - but I cannot get the peerlink up - my config is pretty simple:

!Command: show running-config vpc
!Time: Sat Oct 8 21:18:41 2011

version 5.0(3)N2(1)
feature vpc

vpc domain 5
peer-keepalive destination 172.21.246.53 source 172.21.246.52

interface port-channel25
vpc peer-link

!Command: show running-config vpc
!Time: Sat Oct 8 21:18:41 2011

version 5.0(3)N2(1)
feature vpc

vpc domain 5
peer-keepalive destination 172.21.246.52 source 172.21.246.53

interface port-channel25
vpc peer-link

and I can ping the boxes between them also:

skan5020-01# ping 172.21.246.53 source 172.21.246.52 vrf management
PING 172.21.246.53 (172.21.246.53) from 172.21.246.52: 56 data bytes
64 bytes from 172.21.246.53: icmp_seq=0 ttl=254 time=3.468 ms
64 bytes from 172.21.246.53: icmp_seq=1 ttl=254 time=3.039 ms
64 bytes from 172.21.246.53: icmp_seq=2 ttl=254 time=3.215 ms
64 bytes from 172.21.246.53: icmp_seq=3 ttl=254 time=3.319 ms
64 bytes from 172.21.246.53: icmp_seq=4 ttl=254 time=3.143 ms

--- 172.21.246.53 ping statistics ---
5 packets transmitted, 5 packets received, 0.00% packet loss
round-trip min/avg/max = 3.039/3.236/3.468 ms
skan5020-01#

and the other box:

skan5020-02# ping 172.21.246.52 so 172.21.246.53 vrf management
PING 172.21.246.52 (172.21.246.52) from 172.21.246.53: 56 data bytes
64 bytes from 172.21.246.52: icmp_seq=0 ttl=254 time=5.795 ms
64 bytes from 172.21.246.52: icmp_seq=1 ttl=254 time=7.178 ms
64 bytes from 172.21.246.52: icmp_seq=2 ttl=254 time=7.294 ms
64 bytes from 172.21.246.52: icmp_seq=3 ttl=254 time=4.109 ms
64 bytes from 172.21.246.52: icmp_seq=4 ttl=254 time=7.279 ms

--- 172.21.246.52 ping statistics ---
5 packets transmitted, 5 packets received, 0.00% packet loss
round-trip min/avg/max = 4.109/6.331/7.294 ms
skan5020-02#

the first one tells me this:

skan5020-01# sh vpc peer-keepalive

vPC keep-alive status           : Suspended (Destination IP not reachable)
--Send status                   : Success
--Last send at                  : 2011.10.08 21:21:11 481 ms
--Sent on interface             : mgmt0
--Receive status                : Failed
--Last update from peer         : (2679) seconds, (959) msec

vPC Keep-alive parameters
--Destination                   : 172.21.246.53
--Keepalive interval            : 1000 msec
--Keepalive timeout             : 5 seconds
--Keepalive hold timeout        : 3 seconds
--Keepalive vrf                 : management
--Keepalive udp port            : 3200
--Keepalive tos                 : 192
skan5020-01#

but the other hasn't got any problems:

skan5020-02# sh vpc peer-keepalive

vPC keep-alive status           : peer is alive
--Peer is alive for             : (1271) seconds, (472) msec
--Send status                   : Success
--Last send at                  : 2011.10.08 21:13:19 115 ms
--Sent on interface             : mgmt0
--Receive status                : Success
--Last receive at               : 2011.10.08 21:13:19 121 ms
--Received on interface         : mgmt0
--Last update from peer         : (0) seconds, (833) msec

vPC Keep-alive parameters
--Destination                   : 172.21.246.52
--Keepalive interval            : 1000 msec
--Keepalive timeout             : 5 seconds
--Keepalive hold timeout        : 3 seconds
--Keepalive vrf                 : management
--Keepalive udp port            : 3200
--Keepalive tos

Any suggestions? They are runnging same versions and both have feature vpc and lacp activated

Reza Sharifi · ‎10-08-2011

Hi,

Are you running LACP on the portchannel?

Can you post the physical interface's config that are part of this portchannel?

HTH

tiwang · ‎10-09-2011

hi again

the physical port is setup tis way (only a single to start with):

interface port-channel25
switchport mode trunk
vpc peer-link
switchport trunk allowed vlan 20
spanning-tree port type network

interface port-channel26
switchport mode trunk

interface Ethernet1/1
switchport mode trunk
switchport trunk allowed vlan 20
channel-group 25

brian_allen · ‎10-08-2011

ran into the same issue with a spanning tree link up, you don't need it and it will cause errors

tiwang · ‎10-09-2011

hi again

maybe I have epxlained the problem a little bit wrong - the peerlink is not coming up but this is probably because of the other problem - the vpc peer-kealive connection cannot be established - as you can see on my first post the first switch can send but doesnt receive anything on the keepalvie link but the second sends and receives so form this side it looks ok.

One of my goals was to use as few boxes as possibly so I am using the fex on the first switch as switch to connect the mgmnt-interfaces to also - vlan 20 - could this be the problem?

tiwang · ‎10-12-2011

for those who might be interested in the cause and solution - as I wrote I used a single connected fex on the one nexus as switch to hold the vpc keep-alive link with - thise worked fine for the other nexus's I had in that pod but not for the one which did hold the fex - there is some binding there which might not be obvious..

I added a management-switch for the keep-alive link and put a uplink to the fex and I got the vpc keep-alive and peerlink online in 30 seconds.

best regards /ti