[asterisk-users] SIP TOS Not being set

[Nick Brown]

Hi All,

Facing an issue at the moment with setting the TOS on packets - the documentation is a bit light, however is straightforward so unsure if this is a configuration issue or a bug. 

Following is set in sip.conf;
tos_sip=CS3
tos_audio=EF

And is reflected in the CLI;
IP ToS SIP:             CS3
IP ToS RTP audio:       EF

However a packet capture shows the following;

RTP Packet looks good;
11:39:59.554679 IP (tos 0xb8, ttl  64, id 0, offset 0, flags [DF], proto: UDP (17), length: 200) LOCAL.26392 > REMOTE.8768: UDP, length 172

Signaling Packet not so good;
11:39:59.633869 IP (tos 0x0, ttl  64, id 35957, offset 0, flags [none], proto: UDP (17), length: 479) LOCAL.sip > REMOTE.sip: SIP, length: 451

Seeing the same behavior on 1.4.28 and 1.6.2.9, separate servers. The packet captures are from the box itself so will not be affected by anything upstream.

Anyone able to advise if they see the same problem?

Cheers
Nick.