Cisco C500 Switch Trunking fail after reboot

[jonathanghignoli]

I have a connection between a Cisco c500 and a Cisco 3560 in trunk on a vlan (vlan id 216). When one of the 2 switches is accidentally restarted following an electrical outage, the "switchport mode access" command is added to the trunk port, removing the "switchport mode trunk" command so the switch is no longer reachable.

This is the example:

Switch 1
cdp
Device ID: PB_C500_CET2
Entry address (es):
IP address: 10.20.16.59
Platform: cisco WS-CE500G-12TC, Capabilities: IGMP switch
Interface: GigabitEthernet0 / 1, Port ID (outgoing port): GigabitEthernet12
Holdtime: 171 sec

Version:
Cisco IOS Software, CE500 Software (CE500-LANBASE-M), Version 12.2 (25) SEG6, RELEASE SOFTWARE (fc2)
Copyright (c) 1986-2008 by Cisco Systems, Inc.
Compiled Fri 05-Sep-08 20:31 by myl

advertisement version: 2
VTP Management Domain: 'Piombino'
Native VLAN: 1 (Mismatch)
Duplex: full
Management address (es):
IP address: 10.20.16.59

Switch n1 is configured as follows:

interface Vlan1
no ip address
shutdown
!
interface Vlan216
description *** SWITCH MANAGEMENT ***
ip address 10.20.16.92 255.255.252.0
ip helper-address 10.20.1.1
ip helper-address 10.72.4.20

interface GigabitEthernet0 / 1
description *** Link to C500 CET2 ***
switchport trunk native vlan 216
switchport mode trunk

Switch2 before reboot:
interface GigabitEthernet0 / 12
switchport trunk native vlan 216
switchport mode trunk

interface Vlan1
no ip address
no ip route-cache
shutdown
!
interface Vlan216
ip address 10.20.16.59 255.255.252.0
ip helper-address 10.20.1.1
ip helper-address 10.72.4.20
no ip route-cache

Switch2 after reboot:

Current configuration: 295 bytes
! THIS FILE HAS BEEN GENERATED BY THE GUI.
! ANY CHANGES TO THIS FILE MAY RESULT IN INCORRECT SWITCH BEHAVIOR.
!
interface GigabitEthernet12
description Link to 3560 CET2
switchport trunk native vlan 216
switchport mode access
macro description cisco-other
ip dhcp snooping trust
end
! F16C

interface Vlan1
no ip address
no ip route-cache
shutdown
!
interface Vlan216
ip address 10.20.16.59 255.255.252.0
ip helper-address 10.20.1.1
ip helper-address 10.72.4.20
no ip route-cache

This problem happens often. Please help me. Thank you

[balaji.bandi · Accepted solution]

make sure you write and save the config after changes.

Try defaul the interface and remove the macro and configure again and test it, make sure you write and commit the changes.

interface GigabitEthernet12
description Link to 3560 CET2

switchport mode trunk
switchport trunk native vlan 216
switchport mode access
no macro description cisco-other
ip dhcp snooping trust
end

[jonathanghignoli]

Thanks for your help.
I always did wr whenever I changed the configuration of the C500.
I considered your advice to remove the macro.
Now I'm testing the switch.
I hope I have solved the problem. Thank you

[balaji.bandi]

Glad all went to well, thank you for marking as a solution (which helps other community members to review if they have the same issue - easy to resolve by themself).

[Squozen_EU]

You also have a native VLAN mismatch on the trunk between switches, you want to fix that as well.

[MHM Cisco World]

reboot without save the running-config make SW use start-config and make the trunk go to access BUT
the VLAN info  is save in other memory location and it not change with running-config.