Solved: Cisco Voice VLAN mismatch warnings

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Simon🇨🇦

Cisco Voice VLAN mismatch warnings

We have warnings on some of our Cisco small business network switches; network performance/quality seems to be fine.

[21 Cisco PoE and non-PoE switches SG-200, SG-250HP and SG-500 currently on the network].
VoIP system configured throughout our network that has been up and running for the past 6 months without any problems.
The warning messages are recent, and came up on our SG-500 core switches [Flash memory logs]
Warning is declared as "%CDP-W-VOICE_VLAN_MISMATCH: Voice VLAN mismatch detected on interface X" - where X is the up-link port number connecting to core/edge switch.
Ports affected are all (only) up-links, core to core or core to edge.

* All switches have the latest firmware installed

* All configured with the same VLAN IDs (Default VLAN is 1 & Voice VLAN 30, configured trunk ports, separated tagged from untagged)

* Dynamic voice VLAN disabled on all switches

* Auto voice VLAN disabled on all switches

* CDP enabled on all switches

* Global settings for QoS trust mode is CoS/802.1p

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Sean🇺🇸

Log into to the web configuration utility and choose VLAN Management > Voice VLAN > Properties

Is it set to vlan 30 there?

Or post your config so we can get a better idea.

Simon🇨🇦

ASKER

All switches are set to VLAN 30 under VLAN Management > Voice VLAN > Properties.
I will follow up with config file.

Simon🇨🇦

ASKER

config-file-header
Rack71-1Switch192-0-0-132Stack
v1.4.8.6 / R800_NIK_1_4_202_008
CLI v1.0
set system mode router queues-mode 4
file SSD indicator plaintext
@
vlan database
vlan 2,30
exit
voice vlan id 30
voice vlan state disabled
voice vlan oui-table add 0001e3 Siemens_AG_phone________
voice vlan oui-table add 00036b Cisco_phone_____________
voice vlan oui-table add 00096e Avaya___________________
voice vlan oui-table add 000fe2 H3C_Aolynk______________
voice vlan oui-table add 0060b9 Philips_and_NEC_AG_phone
voice vlan oui-table add 00d01e Pingtel_phone___________
voice vlan oui-table add 00e075 Polycom/Veritel_phone___
voice vlan oui-table add 00e0bb 3Com_phone______________
port-channel load-balance src-dst-mac-ip
bonjour interface range vlan 1
qos trust cos
hostname Rack71-1Switch192-0-0-132Stack
passwords aging 0
snmp-server location "Offc 71\Flr 1\Sctn E\Rm NE-S (\"Server Rm 71\")"
clock timezone " " 0 minutes 0
clock summer-time web recurring usa

interface vlan 1
ip address 192.0.0.132 255.255.254.0
no ip address dhcp

interface vlan 2
name Sister_Company

interface vlan 30
name VoIP

interface gigabitethernet1/1/1
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/2
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/3
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/4
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/5
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/6
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/7
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/8
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/9
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/10
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/11
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/12
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/13
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/14
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/15
switchport trunk allowed vlan add 30
switchport trunk native vlan 2

interface gigabitethernet1/1/16
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/17
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/18
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/19
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/20
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/21
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/22
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/23
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/24
description "Downlink to B71-Switch 192.0.0.126"
switchport trunk allowed vlan add 30

interface gigabitethernet1/1/25
description "Uplink from Rack67-1Switch192-0-0-133Stack1"
channel-group 2 mode on

interface gigabitethernet1/1/26
description "Uplink to Rack85-1Switch192-0-0-131Stack1"
channel-group 1 mode on

interface gigabitethernet2/1/1
switchport trunk allowed vlan add 30

interface gigabitethernet2/1/2
switchport trunk allowed vlan add 30

interface gigabitethernet2/1/3
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/4
switchport trunk allowed vlan add 30
switchport trunk native vlan 2
power inline never

interface gigabitethernet2/1/5
description "IP PBX Primary"
switchport mode access
switchport access vlan 30
power inline never

interface gigabitethernet2/1/6
description "IP PBX Secondary"
switchport mode access
switchport access vlan 30
power inline never

interface gigabitethernet2/1/7
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/8
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/9
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/10
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/11
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/12
description "Downlink to B71-2ndFloor Switch 192.0.0.127"
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/13
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/14
switchport trunk allowed vlan add 30
power inline priority high

interface gigabitethernet2/1/15
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/16
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/17
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/18
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/19
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/20
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/21
switchport trunk allowed vlan add 30
switchport trunk native vlan 2
power inline never

interface gigabitethernet2/1/22
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/23
description "Downlink to B71 Switch 192.0.0.121"
switchport trunk allowed vlan add 30
power inline never

interface gigabitethernet2/1/24
description "Downlink to B71 Switch 192.0.0.125"
spanning-tree link-type point-to-point
switchport trunk allowed vlan add 30
macro description switch
power inline never
next command is internal.
macro auto smartport dynamic_type switch

interface gigabitethernet2/1/25
description "Uplink from Rack67-1Switch192-0-0-133Stack2"
channel-group 2 mode on

interface gigabitethernet2/1/26
description "Uplink to Rack85-1Switch192-0-0-131Stack2"
channel-group 1 mode on

interface Port-channel1
description "Uplink to Rack85-1Switch192-0-0-131Stack"
spanning-tree link-type point-to-point
switchport trunk allowed vlan add 2,30
macro description switch
next command is internal.
macro auto smartport dynamic_type switch

interface Port-channel2
description "Uplink from Rack67-1Switch192-0-0-133Stack"
spanning-tree link-type point-to-point
switchport trunk allowed vlan add 2,30
macro description switch
next command is internal.
macro auto smartport dynamic_type switch

exit

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arnold🇺🇸

The comments from before, deal with all equipment including the router.

All devices routers, switches need to have 30 as the Voice vlan.

There is a mismatch.

Simon🇨🇦

ASKER

The company firewall has a LAN sub zone setup X0:V30 with DHCP. It is part of voice VLAN 30.
There are no errors on the firewall/cisco port.

All core/edge Cisco switches have VLAN 30 as the voice vlan, still the uplink ports show errors.

"There is a mismatch"
Can you please be more specific? How do I find the mismatch?
Thanks,

arnold🇺🇸

usually the uplink should be a trunk that vlan1 and vlan30 pass through, it is not clear that this is what your setup is.

check the uplink port config on the device to which it is connected and how it is configured..

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Simon🇨🇦

ASKER

All the uplink ports with errors are configured the same way:

Trunk
VLAN 1 - Untagged
VLAN 30 - Tagged

arnold🇺🇸

You have to check how you have your setup defined.

Commonly the uplink is a trunk that passes all vlans it should not be tagged........
Check whether the uplink port is configured as a trunk on the switch... and matched on the router to which it is connected. then the chaining of the switch ports that feed the other switches .....

Simon🇨🇦

ASKER

Contacted Cisco small business support.
Cisco confirmed that all ports are in trunk mode, VLAN 1 untagged and VLAN 30 tagged (all set up correctly).

They don't have a solution for me, we are looking into possible "Smartport" feature causing errors after reboots.

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Simon🇨🇦

ASKER

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Simon🇨🇦

ASKER

This is what resolved my issue, Cisco small business support assisted as well.

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