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.

[RosemaryDavis]

Hi @Isaac001,

The confusion is understandable—VOSS handles VLAN membership a bit differently from other systems. Here’s a simple explanation.

Access Port (untagged port):
An access port carries traffic for only one VLAN, and all frames are sent and received untagged. Example:

vlan create 12 type port-mstprstp 0
vlan members 12 1/7
interface gig 1/7
encapsulation dot1q
default-vlan-id 1/7 12
untag-port-default-vlan
exit

This makes port 1/7 an untagged member of VLAN 12—ideal for endpoints like PCs or printers.

Trunk Port (tagged port):
A trunk port carries multiple VLANs, tagging traffic so connected devices can distinguish between them. Example:

vlan create 12,23 type port-mstprstp 0
vlan members 12,23 1/7 portmember
interface gig 1/7
encapsulation dot1q
default-vlan-id 1/7 12
exit

Here, port 1/7 is a trunk that tags VLAN 23 and others, while VLAN 12 is untagged (the native VLAN).

The key difference is that “portmember” adds a tagged VLAN, while without it the port is untagged. Each port can have one untagged VLAN but multiple tagged VLANs.

Best Regards, 

EpyTV

[WillyHe]

Hello,

We are talking VOSS in this discussion

It is and will always be confusing people when talking about TRUNK.
First of all, what is a TRUNK?, a TRUNK is a group/collection/... of things.

• For Cisco oriented people a TRUNK is a group of ports (LAG link aggregation).
• For some others (EXTREME is one of them) they talk TRUNK in regards to a group of vlan's assigned to a port or an MLT (Multi Link Trunk).

So for some people a TRUNK is a group of vlan's, for others it is a group of ports.
First of all when starting discussing TRUNK's, agree in what you understand a TRUNK is.

btw,

• The correct command to add a vlan to a port is "vlan members add 1111 1/25", so vlan first the the port.
• The correct command to add a vlan to an MLT is "mlt 111 vlan 1111".
  In the configuration it will be shown as port and MLT member, see below.

vlan create 1111 name "vlan_1111" type port-mstprstp 0
vlan mlt 1111 111
vlan members 1111 1/11 portmember

• On an untagged or access port vlan info is removed from the outgoing packets.
• On a tagged port, all vlan's can be tagged or all vlan's can be tagged except one which is untagged.

[Isaac001]

Hi @WillyHe 

Thanks for your response! Your explanation was heading somewhere until you mentioned MLT which is something am still grasping. So it threw me off your point.  Kindly use straight forward example of regular port interface. Otherwise, thanks for shedding light on it!👍

Regards,

Isaac.

[WillyHe]

In VOSS, and MLT is equal to etherchannel or LACP static configuration, it groups (trunks 😊) multiple ports in a Link-Aggregation-Group or Multi-Link-Trunk (so here we also talk about "trunk").

To have vlan's tagged/trunked on an MLT, this is enable/disabled on the MLT interface, not on the MLT member ports, the MLT is controlling the ports, at least for a "static" MLT configuration.
When LACP is enabled on an MLT then enable/disable tagging is done on port level.

Every switch OS has his way of doing things, most are similar but there are always (small 🙂) differences.

hope it helps clarifying
WillyHe