Follow up to this Q&A.

According to one of the answers it should be possible to solve a MD5 digest mismatch by synchronizing username, password and domain between VTP Client and Server and subsequently executing a VLAN change on the VTP Server to align the MD5 digest on the Client.

However, after executing these steps and executing sh vtp st on both the VTP Server and the Client a discrepancy between MD5 digest between these two remains, which avoids that the VLAN database on the VTP Client is synchronized with the one of the VTP Server.

Once a name of a VLAN has been changed on the VTP server the MD5 digest will be changed. However, the MD5 digest on the client remains the same and the following message is shown:

*** MD5 digest checksum mismatch on trunk: Po1 ***

2 Answers 2


After checking this thread on the Cisco Learning Network and subsequently executing some checks on both the VTP Client and Server, e.g:

sh vtp st
sh vtp password
sh int trunk

it appears that the domain is identical and the portchannel is in trunking mode. However, there was a discrepancy between the VTP passwords for some reason.

After synchronizing the passwords on the VTP Client and Server by executing vtp password hello and changing a name of a VLAN (conf t && vl X && name helloworld) on the VTP Server, the MD5 digests became identical

Switch#sh vtp st
VTP Version capable             : 1 to 3
VTP version running             : 1
VTP Domain Name                 : domain
VTP Pruning Mode                : Enabled
VTP Traps Generation            : Disabled
Device ID                       : X.Y.Z
Configuration last modified by X at Y Z

Feature VLAN:
VTP Operating Mode                : Client
Maximum VLANs supported locally   : 1005
Number of existing VLANs          : 6
Configuration Revision            : 6
MD5 digest                        : 0xfc 0x5e 0x03 0x8d 0x38 0xa5 0x70 0x32 
                                    0x08 0x54 0x41 0xe7 0xfe 0x70 0x10 0xb0

and the VLAN lists subsequently synchronized.

Switch>sh vl

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Gi0/1, Gi0/2, Gi0/3, Gi0/4
                                                Gi0/5, Gi0/6, Gi0/7, Gi0/8
                                                Gi0/9, Gi0/10, Gi0/11, Gi0/12
                                                Gi0/13, Gi0/14, Gi0/15, Gi0/16
                                                Gi0/17, Gi0/18, Gi0/19, Gi0/20
                                                Gi0/21, Gi0/22, Gi0/23, Gi0/24
                                                Gi0/25, Gi0/26, Gi0/27, Gi0/28
                                                Gi0/29, Gi0/30, Gi0/31, Gi0/32
                                                Gi0/33, Gi0/34, Gi0/35, Gi0/36
                                                Gi0/37, Gi0/38, Gi0/39, Gi0/40
                                                Gi0/41, Gi0/42, Gi0/43, Gi0/44
100  helloworld                       active

Create one more vlan (you can delete it afterwards) and it should resolve your problem

add vlan 999
no vlan 999
  • 1
    How does that solve the problem?
    – Teun Vink
    Commented Mar 13, 2017 at 15:06
  • 1
    @TeunVink it forces a refresh to the clients, if the config is the correct on both sides it will just syncronize
    – aseques
    Commented Aug 18, 2020 at 13:02

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