Category:Cisco Systems -> Routing and Switching
Will VLANs 500 and 600 be moved from Switch B to Switch A according to the following diagram?
Yes, they will.
Here’s a little test.
The initial conditions for Switch A (trunk link to Switch B unplugged):
Switch A#sh vtp st
VTP Version : 2
Configuration Revision : 1
Maximum VLANs supported locally : 255
Number of existing VLANs : 10
VTP Operating Mode : Server
VTP Domain Name : NULL
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0xDE 0x74 0x9A 0x72 0x4B 0x20 0x27 0xE1
Configuration last modified by 192.168.0.1 at 3-1-93 00:31:39
Local updater ID is 0.0.0.0 (no valid interface found)
Switch A#sh vl
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/1, Fa0/2, Fa0/4, Fa0/5
Fa0/6, Fa0/9, Fa0/11, Fa0/12
Fa0/13, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24, Gig1/1
Gig1/2
100 VLAN0100 active Fa0/10
120 VLAN0120 active Fa0/3
155 VLAN0155 active Fa0/14
200 VLAN0200 active Fa0/7
300 VLAN0300 active Fa0/8
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
The initial conditions for Switch B (trunk link to Switch A unplugged):
Switch B(config)#do sh vl
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/1, Fa0/3, Fa0/4, Fa0/5
Fa0/6, Fa0/7, Fa0/8, Fa0/9
Fa0/10, Fa0/11, Fa0/12, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24, Gig1/1
Gig1/2
100 VLAN0100 active
120 VLAN0120 active
155 VLAN0155 active
200 VLAN0200 active
300 VLAN0300 active
500 VLAN0500 active
600 VLAN0600 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
Switch B(config)#do sh vtp st
VTP Version : 2
Configuration Revision : 3
Maximum VLANs supported locally : 255
Number of existing VLANs : 12
VTP Operating Mode : Client
VTP Domain Name : NULL
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0x64 0x22 0xD7 0xB3 0x0F 0x95 0x38 0x5E
Configuration last modified by 0.0.0.0 at 3-1-93 00:04:04
Now let’s physically connect both switches and see if the “server” Switch A with VTP revision 1 renewed its VLAN database from the client Switch B with greater VTP revision number which is 3:
Switch A#sh vl
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/2, Fa0/4, Fa0/5, Fa0/6
Fa0/9, Fa0/11, Fa0/12, Fa0/13
Fa0/15, Fa0/16, Fa0/17, Fa0/18
Fa0/19, Fa0/20, Fa0/21, Fa0/22
Fa0/23, Fa0/24, Gig1/1, Gig1/2
100 VLAN0100 active Fa0/10
120 VLAN0120 active Fa0/3
155 VLAN0155 active Fa0/14
200 VLAN0200 active Fa0/7
300 VLAN0300 active Fa0/8
500 VLAN0500 active
600 VLAN0600 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
So VTP mode client does not necessarily mean that the switch will only import configuration from VTP server mode switch. Thus bringing a VTP client mode switch to the campus, make sure its revision number is lower than that of your production switches or it will corrupt your original VLAN database regardless that it’s only a VTP client switch.
By privilege15