show cdp show cdp neighbors show cdp neighbors detail !clear cdp counters !clear cdp table show cdp entry * protocol show cdp entry * version
eventually disable CDP
config t no cdp run no cdp advertise-v2 exit
or per interface
config t interface fa0/X switchport nonegotiate end
only pass the VTP advertisements through trunks
vtp mode transparent !set vtp mode transparent
check your configuration
show run | include vtp show run | include vlan !show interfaces show interface fa0/1 show interface fa0/24 show interface gi0/1 show interface gi0/1 trunk show interface gi0/2 show interface gi0/2 trunk
check your VTP Version, Domain, Revision
show vtp status
check operations and password setting
show vtp counters show vtp password
Chapter: CDP Commands https://www.cisco.com/c/en/us/td/docs/ios/12_2/configfun/command/reference/ffun_r/frf015.html
show cdp neighbors https://www.cisco.com/c/m/en_us/techdoc/dc/reference/cli/nxos/commands/l2/show-cdp-neighbors.html
How could I know what is the native-vlan on the neighbor device? https://learningnetwork.cisco.com/thread/117744
CDP Neighbor over multiple vlans https://community.cisco.com/t5/other-network-architecture/cdp-neighbor-over-multiple-vlans/td-p/3082829
Disabling Dynamic Trunking Protocol (DTP) https://www.freeccnaworkbook.com/workbooks/ccna-security/disabling-dynamic-trunking-protocol-dtp
Disable DTP on a switch https://community.cisco.com/t5/switching/disable-dtp-on-a-switch/td-p/3328521
Understanding VLAN Trunk Protocol (VTP) https://www.cisco.com/c/en/us/support/docs/lan-switching/vtp/10558-21.html
Configuring VLAN Trunk Protocol (VTP) https://www.cisco.com/c/en/us/support/docs/lan-switching/vtp/98154-conf-vlan.html
Troubleshooting VLAN Trunk Protocol (VTP) https://www.cisco.com/c/en/us/support/docs/lan-switching/vtp/98155-tshoot-vlan.html
Cisco Discovery Protocol Configuration Guide, Cisco IOS Release 15M&T https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/cdp/configuration/15-mt/cdp-15-mt-book/nm-cdp-discover.html
How a Recently Inserted Switch Can Cause Network Problems https://www.cisco.com/c/en/us/support/docs/lan-switching/vtp/98155-tshoot-vlan.html#topic7
Reset the Configuration Revision Number https://www.cisco.com/c/en/us/support/docs/lan-switching/vtp/98155-tshoot-vlan.html#topic9
Switches not updating VLAN’s https://community.cisco.com/t5/other-network-architecture/switches-not-updating-vlan-s/td-p/510505
The VLAN configuration changes do not update on a switch due to the misconfiguration of the VTP and the “VLAN 1003 parent VLAN missing” error message appears https://community.cisco.com/t5/networking-documents/the-vlan-configuration-changes-do-not-update-on-a-switch-due-to/ta-p/3131447