WS-C3650-24TS-L vrf forwarding Mgmt-vrf Issue

[tanner.zaitt]

Hello all.
I am in trouble with WS-C3650-24TS-L and vrf forwarding Mgmt-vrf Issue.
I couldn't find a solution and a reason for this behavior.

Switch A is WS-C3650-24TS-L  and the Switch B is WS-C2960X-48LPS-L.
Switch A and B are connected to each other with a cable.

SwitchA#G0/0 <---------->SwitchB#G1/0/48

SwitchA port configuration:
interface GigabitEthernet0/0
vrf forwarding Mgmt-vrf
ip address 10.10.10.2 255.255.255.128
no ip redirects
no ip unreachables
no ip proxy-arp
negotiation auto
end

The default gateway of Switch A
ip default-gateway 10.10.10.1
The static route of Switch A
ip route vrf Mgmt-vrf 0.0.0.0 0.0.0.0 10.10.10.1

SwtichB port configuration
interface GigabitEthernet1/0/48
description UP_2_Switch_A
switchport access vlan 2002
switchport mode access
no logging event power-inline-status
snmp trap mac-notification change added
snmp trap mac-notification change removed
end

Switch B L3 interface:
interface Vlan2002
ip address 10.10.10.3 255.255.255.128
end
The default gateway of Switch B
ip default-gateway 10.10.10.1

The Switch A is with Denali 16.03.11 ios image.
The Switch B is with 15.0(2)EX5 ios image.
The bad behavior is that we often receive alarms for connection lost to Switch A for under 5 minutes.
We have few switches configured to comunicate between each other in this way and all they are affected with this behavior.
Do you have any idea?

[Reza Sharifi]

Hi,

Switch B L3 interface:
interface Vlan2002
ip address 10.10.10.3 255.255.255.128

ip route vrf Mgmt-vrf 0.0.0.0 0.0.0.0 10.10.10.1
on Switch A, the default gatewsy should be 10.10.10.3 if switch B supposed to be the gateway.

ip route vrf Mgmt-vrf 0.0.0.0 0.0.0.0 10.10.10.3

If not where is 10.10.10.1 located?

HTH

[tanner.zaitt]

Hi,

10.10.10.1 is the IP of the core switch of the internal network.

[Reza Sharifi]

Ok, so do you have a trunk port connecting switch-B to the core switch and extending vlan 2002?

HTH

[tanner.zaitt]

Yes, trunk between B and Switch C, switch C has trunk to Switch D, Switch D has trunk to the Core Switch.

[Reza Sharifi]

switch-A(10.10.10.2 in mgmt vrf)------switch-B(layer-2)------switch-C(layer-2)------switch-D(layer-2)------switch-E(Core10.10.10.1 layer-3)

If this is the design and you have redundant connections, look for a loop someplace on the network.

HTH

[tanner.zaitt]

Yes, I search for it now.
I will share more details.