MC connection issue after upgrade from 3.1 to 3.2

Products

• Management Center
• Management Center - VA

Issue/Introduction

After upgrade from MC 3.1 to 3.2 , no communication to the Management center from IP 172.17.0.0/16

Cause

The root cause of this issue is due to the bridge interface on the Management Center with IP 172.17.0.1/16

docker0    inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0\       valid_lft forever preferred_lft forever

The return traffic will use this interface as a direct attached network rather than using the default GW configured on the MC

Resolution

The work around would be to add a static route for the network you have issue with to use the default GW IP 

e.g.

MC(config)# ip route 172.17.0.0/17 192.168.2.1

Additional Information

Sample captures:

 

Default gateway not followed  towards 172.17.0.2 

mc11# show running-config interface

interface 0:0

  enable

 dhcp     disable

 speed  auto

 duplex auto

 mtu-size 1500

 ip-address 192.168.2.11 255.255.255.0

 mc11# show running-config ip

ip default-gateway 192.168.2.1

 

mc11# ping 172.17.0.2

PING 172.17.0.2 (172.17.0.2) 100(128) bytes of data.

From 172.17.0.1 icmp_seq=1 Destination Host Unreachable

From 172.17.0.1 icmp_seq=2 Destination Host Unreachable

 

Workaround applied:

mc11# configure t

Enter configuration commands, one per line. End with CNTL/Z.

mc11(config)# ip route 172.17.0.0/17 192.168.2.1   

mc11(config)# exit

 

Route towards 172.17.0.2 is now exiting default gateway

mc11# show running-config ip

ip default-gateway 192.168.2.1

ip route 172.17.0.0/17 192.168.2.1

 

mc11# ping 172.17.0.2

PING 172.17.0.2 (172.17.0.2) 100(128) bytes of data.

108 bytes from 172.17.0.2: icmp_seq=1 ttl=58 time=4.61 ms

108 bytes from 172.17.0.2: icmp_seq=2 ttl=58 time=5.35 ms

mc11#