Hello - happy Friday!
I'm familiar with the command below which tells connected phones to use the 'Voice' Vlan and send voice packets with DSCP set to 46.
"configure lldp port [port] advertise vendor-specific med policy application voice vlan [vlan] dscp 46"
However it appears that XOS sends a dot1p value of 7 (network control traffic) to the phone by default and I can't find out how to change that - I want it set to 5 which is more commonly used for Voice.
# assuming you want to assign 5 to the dot1p field, could you try the folloing to propagate the value of the dot1p value of 5 via LLDP MED,
Create qosprofile QP6
configure dot1p type 5 qp6
# assuming lldp is already configured
configure lldp ports [all | port_list] advertise vendor-specific med capabilities
configure lldp ports [all | port_list] advertise vendor-specific med policy application voice vlan voice dscp dscp_value 46
# configure the voice vlan to QP6 -> then the phone should hopefully start using dot1p=5
Configure vlan voice qosprofile qp6
Thanks JS, that seems to work!
Not sure at the moment if I'll implement it, as we're already using QP6 for all Voice traffic and QP4 for all Voice-Signalling traffic. So, if I mark the whole 'Voice' Vlan as QP6 both RTP & Signalling will be treated with the top priority, not necessarily something I'm looking for.
One question though, assuming the phone sends through a frame with a dot1p value of 7, what will the switch do with it under default configuration?
- all dot1p values but 7 are affected to QP1 ; 7 is affected to QP8
- dot1p examination is enabled
so taking classification precedence into consideration [table 91 - 16.1 userguide] and assuming you don't have any ACL- based QOS classification, I would suggest "dot1p=7 tagged" traffic should be sent to QP8.
the mapping table [dot1p <> QP] can be seen with "show dot1p"