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Original Message:
Sent: May 21, 2025 01:54 AM
From: Owais101
Subject: Cisco Switch Voice Vlan
In your environment are you assigning different vlans to ip phones and different vlans to PC? like 1001 to ip phone and 200 to PC on the same port using multi-auth?
Original Message:
Sent: 5/21/2025 1:50:00 AM
From: shpat
Subject: RE: Cisco Switch Voice Vlan
In my environment, we have authentication host-mode multi-domain, and we implemented unmanaged switches behind the port (which is not recommended most of the cases) where we had two/three IP Phones, with PC connecting behind it (so total of 4-8 devices), and it worked without any issue.
In the Cisco C1000 guidline it states that:
- Multi-auth mode should be configured to allow devices behind a hub to obtain secured port access through individual authentication. Only one voice device can be authenticated in this mode if a voice VLAN is configured.
- Multi-domain mode should be configured if data host is connected through an IP phone to the port. Multi-domain mode should be configured if the voice device needs to be authenticated.
- Multi-host mode also offers port access for multiple hosts behind a hub, but multi-host mode gives unrestricted port access to the devices after the first user gets authenticated.
So in your case, try Multi-Auth and/or Multi-Domain because it depends what type of IP Phone you are using and how it behaves.
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Shpat | ACEP | ACMP | ACCP | ACDP
Just an Aruba enthusiast and contributor by cases
If you find my comment helpful, KUDOS are appreciated.
Original Message:
Sent: May 21, 2025 01:44 AM
From: Owais101
Subject: Cisco Switch Voice Vlan
Dear Shpat,
I understand now and just wanted to make sure we are on the same page.
If i am using host-mode multi-domain, then there will be only 1 device in voice vlan and 1 device in data vlan. Since i have a laptop connected to ip phone, i cannot assign a data vlan to ip phone because then the laptop will not authenticate (1 device per domain). If i change the host-mode to multi-auth, i cannot assign different vlans to different devices connecting to data domain. I am not sure if its changed in C1000, but i was testing in my lab with 3560 and i found some documentation stating exactly that.
I also saw Herman's post suggesting using normal vlans instead of Voice Vlan, i liked the idea but then i am not able to assign different vlan to ip phone and different vlan to laptop if i am using host-mode multi-auth.
Best Regards
Owais Iqbal
CCIE#37956 | ACDX
Technical Consultant - Aruba Networks
Mob/Whatsapp: +92-321-2960496
Original Message:
Sent: 5/21/2025 1:36:00 AM
From: shpat
Subject: RE: Cisco Switch Voice Vlan
Explaining it in a simple way, Voice-VLAN is like all other VLAN but with this you just have the tagging which enables QoS purposes and also you can make the switch put the Voice devices (if the switch can detect that it is a voice device) go through the voice vlan.
If you want to create a Voice VLAN, lets say VLAN=1000, but you don't want to have the configuration on the port (switchport voice vlan 1000), then you need to send attributes Tunnel-Type = VLAN (13) & Tunnel-Medium-Type = IEEE-802 (6) & Tunnel-Private-Group-Id=1000, and you will make sure that VLAN1000 will be enforced only for Voice devices which are profiled/role mapped and enforced from Clearpass.
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Shpat | ACEP | ACMP | ACCP | ACDP
Just an Aruba enthusiast and contributor by cases
If you find my comment helpful, KUDOS are appreciated.
Original Message:
Sent: May 21, 2025 01:26 AM
From: Owais101
Subject: Cisco Switch Voice Vlan
Also in your statement,
With Cisco 1000 (and i have implemented a lot of them) you either have to push a VLAN (without including device-traffic-class=voice) this will not be a voice vlan right? or you need to push just the line device-traffic-class=voice (without pushing the VLAN).
Original Message:
Sent: 5/21/2025 12:27:00 AM
From: shpat
Subject: RE: Cisco Switch Voice Vlan
Yes, it will assign dynamically the Voice VLAN, if there is a Voice VLAN configured in the Port.

What you are doing with this configuration is that:
You are pushing VLAN 222
You are pushing device-traffic-class=voice (which means you are telling the switch that this device is for Voice purpose place it in Voice VLAN)
However, on your configuration in the switch, the port has no Voice VLAN Configured, therefor it won't place it in the Voice VLAN.
With Cisco 1000 (and i have implemented a lot of them) you either have to push a VLAN (without including device-traffic-class=voice) or you need to push just the line device-traffic-class=voice (without pushing the VLAN).
In addition, there are devices which do not understand the Voice VLAN (old Yealink Phones, old Grandstream) which i faced a lot of issues, where i had to adapt different enforcements. In such cases we only push VLAN (and we do not push device-traffic-class=voice). This means that those devices do not understand voice devices as voice, but you need to put them as data device.
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Shpat | ACEP | ACMP | ACCP | ACDP
Just an Aruba enthusiast and contributor by cases
If you find my comment helpful, KUDOS are appreciated.
Original Message:
Sent: May 21, 2025 12:20 AM
From: Owais101
Subject: Cisco Switch Voice Vlan
Dear Shpat
In my clearpass profile, i am sending vlan 222 with device class traffic voice. Wont it dynamically assign the voice vlan?
Original Message:
Sent: 5/21/2025 12:01:00 AM
From: shpat
Subject: RE: Cisco Switch Voice Vlan
if you will push Cisco-AVPair = device-traffic-class=voice, the switch will search for Voice VLAN.
Your configuration does not contain a Voice VLAN.
interface FastEthernet0/1
switchport mode access
switchport voice vlan 222
authentication host-mode multi-domain
authentication order dot1x mab
authentication priority dot1x mab
authentication port-control auto
authentication timer reauthenticate server
mab
dot1x pae authenticator
dot1x timeout tx-period 10
dot1x timeout supp-timeout 15
dot1x max-reauth-req 1
So if y ou choose to go with AVPair device-traffic-class=voice, you will need to configure the Voice VLAN in the port. If you don't want the Voice VLAN on the Port, then all you need to do is remove the 6. Cisco-AVPair and thats it.
Additionally, you are using IBNS 1.0 format. This is an old format of configuration in Cisco which will soon be deprecated. I would recommend to move to IBNS2.0 (if its Cisco 1000 it supports it). On IBNS 2.0 you would need to configure Policy Maps and then assign the Policy Map in the Port. One example:
The port configuration:
interface range GigabitEthernet1/0/1-23
switchport access vlan <default untrusted vlan>
switchport mode access
switchport nonegotiate
switchport voice vlan 222
ip device tracking maximum <whatever number you need>
authentication periodic
authentication timer reauthenticate server
access-session control-direction in
access-session closed
access-session port-control auto
mab
no macro auto processing
dot1x pae authenticator
dot1x timeout quiet-period 30
dot1x timeout server-timeout 30
dot1x timeout tx-period 7
dot1x max-req 3
dot1x max-reauth-req 3
spanning-tree portfast edge
service-policy type control subscriber CLEARPASS_POLICY_MAP
ip dhcp snooping limit rate 20
!
The Policy Configuration:
policy-map type control subscriber CLEARPASS_POLICY_MAP
event session-started match-all
10 class always do-until-failure
10 authenticate using dot1x priority 10
20 authenticate using mab priority 20
event authentication-failure match-first
5 class DOT1X_FAILED do-until-failure
10 terminate dot1x
20 authenticate using mab priority 20
10 class DOT1X_FAILED do-until-failure
10 terminate dot1x
20 class MAB_FAILED do-until-failure
10 terminate mab
20 authenticate using dot1x priority 10
30 class DOT1X_NO_RESP do-until-failure
10 terminate dot1x
20 authentication-restart 60
40 class always do-until-failure
10 terminate mab
20 terminate dot1x
30 authentication-restart 60
60 class always do-until-failure
10 terminate dot1x
20 terminate mab
30 authentication-restart 60
event agent-found match-all
10 class always do-until-failure
10 terminate mab
20 authenticate using dot1x priority 10
event authentication-success match-all
10 class always do-until-failure
10 activate service-template DEFAULT_LINKSEC_POLICY_SHOULD_SECURE
event aaa-available match-all
10 class IN_CRITICAL_AUTH do-until-failure
10 clear-session
20 class NOT_IN_CRITICAL_AUTH do-until-failure
10 resume reauthentication
event inactivity-timeout match-all
10 class always do-until-failure
10 clear-session
event violation match-all
10 class always do-until-failure
10 restrict
event authorization-failure match-all
10 class AUTHC_SUCCESS-AUTHZ_FAIL do-until-failure
10 authentication-restart 60
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Shpat | ACEP | ACMP | ACCP | ACDP
Just an Aruba enthusiast and contributor by cases
If you find my comment helpful, KUDOS are appreciated.
Original Message:
Sent: May 20, 2025 12:25 PM
From: Owais101
Subject: Cisco Switch Voice Vlan
Dear Experts,
We are trying to implement 802.1x using cisco switch (C1000). Laptop is connected to ip phone (Dlink) and ip phone is connected to switchport. Below is the configuration on cisco switch. Please note that we want to dynamically assign the voice vlan. If port assignment is mandatory let me know
interface FastEthernet0/1
switchport mode access
authentication host-mode multi-domain
authentication order dot1x mab
authentication priority dot1x mab
authentication port-control auto
authentication timer reauthenticate server
mab
dot1x pae authenticator
dot1x timeout tx-period 10
dot1x timeout supp-timeout 15
dot1x max-reauth-req 1
On successful mac authentication, we are sending this profile to switch

Currently upon successful mac auth, the ip phone is not registering to pbx. The customer is already running LLDP/Voice vlan on other switches. This setup is for ClearPass PoC.
Can someone point out if its a configuration issue (clearpass or switch)?
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Owais101
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