Re: [Astlinux-users] VLAN's and 802.1p priority

[Kristian K. <kri...@gm...>]

On 5/17/07, Lonnie Abelbeck <li...@lo...> wrote:
> Hopefully this is of general academic interest...
>
> I currently have many SPA-942 IP Phones and AstLinux (net4801) all
> connected via VLAN capable switches, networked on VLAN20.  My VLAN's
> are routed via m0n0wall (net4801) through a "tagged only" ethernet port.
>
> But, the ethernet ports of the phones and net4801 are untagged, the
> switches are configured to add/strip the VLAN tags at the last few
> meters.
>
> This all works well... but I have an Obsessive Network Tweaking
> Disorder ;) .  All my switches prioritize egress traffic based on the
> 802.1p bits added along with the VLAN ID tag.
>
> So, would I be smart in making all my internal voice traffic, VLAN
> tagged from phone to Astlinux (end to end)?   Easily done in the
> SPA-942's.
>
> In AstLinux I assume:
> VLANS="eth0.20"
> EXTIF="eth0.20"
>
> Would work in PBX only mode?
>
> Question:  What does AstLinux set the 802.1p priority tags to?  Does
> asterisk sense the VLAN and set the 802.1p priority to 5 or 6 like
> the SPA-942 does?
>
>  From a practical point of view, I doubt it makes much difference in
> my situation, but learning is half the fun.
>
> Any experience is appreciated.
>
> Lonnie
>

Lonnie,

  AstLinux doesn't currently set 802.1p priorities on VLANs.  There
isn't even a config variable for it.  In linux, however, all you have
to do is set the correct value with vconfig:

vconfig set_egress_map eth0.41 1 5

  How about something like this:

EPRIO="eth2.41:5"

etc, etc, etc?

  Asterisk does not set layer 2 (802.1p) priority, but it does set
layer 3 (DSCP/IP TOS) with tos= in sip.conf, iax.conf, etc.  How are
your switches / routers configured for that?

-- 
Kristian Kielhofner