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New Member

SLM2008 - native vlan?

I have some issues setting up the Cisco SLM2008 trunking.

My topology:

Router....................... SLM2008 ----------------- PC

............... = trunk

vlan 1, vlan 2, vlan 3

Now - I set up Port2 on the SLM2008 as a trunk (added this port to all vlans and checked 'tagged only', pvid=1

I connected my PC to Port 6 (vlan3) = OK

I connected my PC to Port 8 (vlan1) = does not work

It does work for vlan3 but does not work for my native vlan (vlan1, or vlan2, I tried with two routers). How can I set up my SLM2008 to force e.g. vlan 2 to be a native vlan?

What is strange... when I connect SLM2008 and PC to ports in vlan1 it does work (no trunk on SLM20008, trunk on the router only) - it is recognized by the router as a native vlan1


SLM2008 - native vlan?


I assume that the TRUNK is between the router and the SLM port 2.

Try changing the port to accept "ALL TYPES" of frames.

Also check the config of the routers interface for encapsulation
on the correct vlan numbers.


Regards, Alex. Please rate useful posts.
New Member

SLM2008 - native vlan?

Thx. The problem is that I need to have a native (untagged) vlan as the router is set up to accept vlan 3 + a native vlan. Any idea if it is achievable on this switch?

The trunk to the router was checked with a Cisco AP and it does work


SLM2008 - native vlan?


The native Vlan for a trunk is indicated by PVID for that port (in your case Port 2). But this is only the "sending  side". To enable the trunk fully work with the native vlan "both sides" you need to change the Port 2 setting from "Tagged Only" to "All" as already indicated by other post (that was most likely your initial configuration issue when a PC at Port 8 could not communicate). Also please remember there should only be 1 native Vlan (generally the untagged frame) within the 802.1Q trunk. All this expects that the "Enable Tx Force Untag" setting is at its "Disable" default value.

Best regards,