VLAN & VTP Basics

Creating VLANs is an easy task, but you may run into issues with the VLANs populating between the other access switches (VTP : Client).

Option One (used to create the VLAN)

**Option One**
(config)#vlan 10
(config-vlan)#name SALES

&

**Option Two** 
(config)#interface vlan 10
(config-if)#description SALES
(config-if)#ip address a.b.c.d x.x.x.x

Option two allows you to set a static interface for IP routing. 


For EXTENDED VLANs(1006-4096), VTP mode must be in Transparent. Server mode should throw errors, probably not in IOL devices.

(config)#vtp mode transparent

By default all cisco catalysts come preconfigured with VTP server mode. You will need to change this on all access switches not serving vlans. First,

(config)#vtp mode Server
or
(config)#vtp mode Transparent
or
(config)#vtp mode Client

then, set the domain

(config)#vtp domain CISCO

This will put the switch in client mode and on the same domain as the VTP server. Allowing it to accept VLAN configs from the core or Firewall. If you run into an MD5 digest checksum mismatch error, you may need to change the password on all devices in the same domain that need VTP configs, like this: 

(config)#vtp password cisco

You will then want to issue the below command to show the current status: 

#show vtp status
Sw1>sh vtp status
VTP Version capable             : 1 to 3
VTP version running             : 1
VTP Domain Name                 : CISCO
VTP Pruning Mode                : Disabled
VTP Traps Generation            : Disabled
Device ID                       : aabb.cc00.1200
Configuration last modified by 0.0.0.0 at 7-5-19 23:13:37
Local updater ID is 0.0.0.0 (no valid interface found)


Feature VLAN:
--------------
VTP Operating Mode                : Server
Maximum VLANs supported locally   : 1005
Number of existing VLANs          : 9
Configuration Revision            : 0
MD5 digest                        : 0x87 0x6A 0xFA 0xCB 0xD3 0x27 0xDF 0x0C
                                    0x04 0xF4 0x94 0x8E 0x18 0xEA 0xE9 0x84

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