Voss Access/Trunk Port configuration

[Isaac001]

Hi Support,

I have gone through the extreme documentation but still the configuration between access port and trunk port in VOSS cli is really confusing to me.

For example:

vlan members 23 1/7 portmember I think refers to trunk port configuration on port 1/7

This article:https://extreme-networks.my.site.com/ExtrArticleDetail?an=000104947   Further adds to the configuration.

In the documentation, the there is also this Example:

!

For untagging the port in a VLAN:
#vlan create 12 type port-mstprstp 0 (Create VLAN and type)
#vlan mem 2/2 12 (Add it as a member)
#int gig 2/2
#encapsulation dot1q
#default-vlan-id port 2/2 12 (Specifying that vlan 12 is the default untagged vlan OR Native VLAN)
#untag-port-default-vlan (Specifying that vlan 12 will be used as untagged)
#exit

!

Kindly clarify with clear examples of the differences between access port and trunk port interface configuration in voss.

Thank you all!

Isaac.

[WillyHe · Accepted solution]

Hello,

Are we using VOSS commands here???

The only way to configure a trunk or tagged port or an access or untagged port in VOSS is

VOSS_SWITCH-01:1(config-if)#interface gigabitEthernet 1/25
VOSS_SWITCH-01:1(config-if)#encapsulation dot1q
VOSS_SWITCH-01:1(config-if)#no encapsulation dot1q

Switchport, I think, is a Cisco command.

In VOSS (and also BOSS ERS), the default-vlan-id is always configured.
- When it is an access port then the default-vlan-id = automatically the to that port assigned vlan id and this cannot be changed.
- When it is a tagged or trunk port the default-vlan-id is also configured on the port but it has no meaning or effect unless untag-port-default-vlan is configured, then packets originating from the default-vlan-id are send out untagged (often used to tagg packets for an IP phone and untag packets for a PC connected behind the IP phone).

As an example I configured vlans 3000 3001 and 4000 on port 1/25 and configured vlan 4000 to be untaged.

SMC-MCN-003-01:1#show interfaces gigabitEthernet vlan 1/25
************************************************************************************
Command Execution Time: Tue May 28 21:48:55 2024 CEST
************************************************************************************
====================================================================================================
Port Vlans
====================================================================================================
PORT           DISCARD  DISCARD    DEFAULT  VLAN           PORT    UNTAG    DYNAMIC  UNTAG
NUM   TAGGING  TAGFRAM  UNTAGFRAM  VLANID   IDS            TYPE    DEFVLAN  VLANS    VLANS
----------------------------------------------------------------------------------------------------
1/25  enable   false    false      4000    3000,3001,4000  normal  enable   P        4000
----------------------------------------------------------------------------------------------------
DYNAMIC VLAN Legend:
P=Protocol enabled.
SMC-MCN-003-01:1#

[Isaac001]

Hi @jeannette9728mi 

Thanks for your response, the explanation helped a lot as I am from a Cisco background and I think you were trying to respond in that way. However @gfriedl  mentioned about the default-vlan-id and it threw me off a bit  and the difference between vlan member 1/1 10 and vlan member add/remove 10  as mentioned by @WillyHe  Otherwise thanks for shedding more light on it!👍 You can share more information about this?

Regards,

Isaac.

Regards,

Isaac.

[gfriedl]

correct configuration examples, but not for Extreme VOSS 😉

there is no "switchport mode" command in VOSS.

instead one would need to use "no ecapsulation dot1q" for access port (no trunk), and "encapsulation dot1q" for trunk.

if one than adds such ports to vlan(s), an access port would "move" from current /previously assigned VLAn to the new.

A trunk port would just add this VLAN additionally to the existing VLANs on the trunk port.

the "default-vlan-id" prameter is only relevant (and configurable), when encaps dot1Q is enabled on port.

It is required, if one wants a dedicated untagged vlan on this trunk ; this requires "untag-port-default-vlan enable" for the interface to be used on this port. otherwise the default-vlan-id is irrelevant.

hope this help,

[Isaac001]

Hi @gfriedl 

Thank you for your response. The information is still not that clear to me about the difference between access and trunk port in voss. So far from  the replies I have noticed that trunk port  should have encapsulation dot1q but access port no encapsulation dot1q.  @WillyHe also mentioned that "The correct command to add a vlan to a port is "vlan members add 1111 1/25,so vlan first the port" Kindly comment on this for clarification.

I did a test configuration on a test VOSS switch and the output was surprising to me. Port 1/3 has default-vlan-id 10  Its supposed to be a trunk port so why does it have its default as 10?

Kindly see the configuration I did and output of show port vlan and snippets of running config. I would appreciate if you would share a sample standard configuration that would differentiate access and trunk ports if my is not that good. Thanks👍

===THE WAY I CONFIGURED===
!
vlan create 10 type port-mstprstp 0
vlan create 20 type port-mstprstp 0
!
int g1/1
no encapsulation dot1q
exit
!
int g1/2
no encapsulation dot1q
exit
!
vlan member 10 1/1
vlan member 20 1/2
!
int g1/3
encapsulation dot1q
exit
!

======SHOW PORT VLAN AND SECTION PORT RUNNING CONFIG=======

====================================================================================================
Port Vlans
====================================================================================================
PORT DISCARD DISCARD DEFAULT VLAN PORT UNTAG DYNAMIC UNTAG
NUM TAGGING TAGFRAM UNTAGFRAM VLANID IDS TYPE DEFVLAN VLANS VLANS
-----------------------------------------------------------------------------------------------------------
1/1 disable false false 10 10 normal disable P 10
1/2 disable false false 20 20 normal disable P 20
1/3 enable false false 10 10,20 normal disable P
#
# VLAN CONFIGURATION
vlan members remove 1 1/1-1/42,2/1-2/42 portmember
vlan create 10 type port-mstprstp 0
vlan members 10 1/1,1/3 portmember
vlan create 20 type port-mstprstp 0
vlan members 20 1/2-1/3 portmember
vlan create 4048 name "onboarding-vlan" type pvlan-mstprstp 0 secondary 4049
vlan i-sid 4048 15999999
#
# PORT CONFIGURATION - PHASE I
interface GigabitEthernet 1/3
encapsulation dot1q
exit
# PORT CONFIGURATION - PHASE II
interface GigabitEthernet 1/1
no shutdown
exit
interface GigabitEthernet 1/2
no shutdown
exit
interface GigabitEthernet 1/3
default-vlan-id 10
no shutdown
exit

[gfriedl]

your examples are fine. so 1/1 and 1/2 have tagging disabled, which means these are access (not trunk) ports.

Port 1/3 has encapsulation dot1q enabled, so is in trunk mode.

regarding PVID: if a trunk was never attached to any VLAN, the PVID is just 0. if it was assigned, it changes to this vlan and it stays so, when you add other VLANs to the trunk. you might chnage it anytime and this is necessary, when you want/must use untagged native VLANs, which on VOSS is defined by this PVID. To use untagged native vlan, you must specify it by PVID and also set "untag-port-default-vlan" on this port (or mlt).