Monday, October 24, 2016

Troubleshooting VTP Version 3

 Problem: Switches are working fine after the initial configuration all VLANs are synchronized. Network is working properly. No change is applied after the initial configuration. The problem occurs when trying to add an additional switch and VLANs are not synching on the new switch.

Trunks are fine, vtp domain name and password is configured correctly. All switches and additional switch is configured vtp version 3 assuming one of them is configured as vtp server and the rest are clients. 


Show VTP Status from one of the switch:

SW01#show vtp status
VTP Version capable             : 1 to 3
VTP version running             : 3
VTP Domain Name                 : TEST
VTP Pruning Mode                : Enabled
VTP Traps Generation            : Enabled
Device ID                       : 28c7.xxxx.xxxx

Feature VLAN:
--------------
VTP Operating Mode                : Client
Number of existing VLANs          : 14
Number of existing extended VLANs : 0
Maximum VLANs supported locally   : 1005
Configuration Revision            : 0
Primary ID                        : 0000.0000.0000
Primary Description               :
MD5 digest                        : (note the MD5 digest is empty including the rest of the switches)


Feature MST:
--------------
VTP Operating Mode                : Transparent

Debug:
SW01#debug sw-vlan vtp ?
  events      vtp events
  packets     vtp packets
  pruning     vtp pruning events
  redundancy  vtp redundancy
  xmit        vtp packets transmitted

Debug output:
vtp dropping the packet 3
Fix:
Checking the rest of the switch nothing is configured as vtp primary server. Configuring the appropriate switch as the vtp primary server resolve the problem. The new switch started to receive VTP advertisement packets.

SW01#vtp primary
This system is becoming primary server for feature vlan
No conflicting VTP3 devices found.
Do you want to continue? [confirm]

SW01#show vtp status
VTP Version capable             : 1 to 3
VTP version running             : 3
VTP Domain Name                 : TEST
VTP Pruning Mode                : Enabled
VTP Traps Generation            : Enabled
Device ID                       : 885a.xxxx.xxxx

Feature VLAN:
--------------
VTP Operating Mode                : Primary Server
Number of existing VLANs          : 14
Number of existing extended VLANs : 0
Maximum VLANs supported locally   : 4094
Configuration Revision            : 1
Primary ID                        : 885a.xxxx.xxxx
Primary Description               : SW01
MD5 digest                        : 0x0F 0x0B 0xFA 0xC9 0x96 0x32 0x69 0x29
                                    0x62 0x85 0x38 0x73 0x1A 0x47 0x05 0x59





Friday, October 21, 2016

Connecting Virtualbox Guests to GNS3

Under VirtualBox Manager Adapter1 Settings.
1. Enable Network Adapter
2. Not attached
3. Adapter Type: PCnet-FastIII



 Settings under GNS3 Node Properties
1. Adapter type should match with VirtualBox Settings.




 Test by pinging the default gateway.