Procurve/Provision: ILLEGAL 802.1Q VLAN tagging

[dts3909]

https://support.hpe.com/hpsc/doc/public/display?sp4ts.oid=null&docLocale=en_US&docId=emr_na-a00038722en_us

Page 251:   "Override "illegal" packet priorities set by upstream devices or applications that use 802.1Q VLAN tagging 802.1p priority tags."

What are "illegal" packet priorities?

More importantly:  How does one OVERRIDE them?

Thanks in advance.

[Vince-Whirlwind]

For example, you might have a user who ius running a video-conferencing software app on their desktop, and that software might allow the user to set his own DSCP/IP precedence vlues on the packets generated from that software. The user might think, "Ha, I'm going to set everything to the max so I get full priority". You then have the potential issue of 

 - voice and video traffic flooding the highest-priority, very low-bandwidth, switch queue which is designed to carry critical network messaging>
 - video traffic flooding the priority, low-bandwidth, queue designed to carry voice.

The document you are reading describes how you override those bad values:
1/ identify the traffic type using access lists
2/ use classifiers to match access-list matches to classes
3/ use policy actions to assign values as per the identified classification.
The policy action would identify, as an example,
 - voice RTP traffic and assign it ip precedence "6" ("5" in a mixed vendor network), DSCP EF(46)
 - video traffic "5" and AF41(34)
 - media signalling "3" and AF31(26)
 - default traffic "0" and BE(0)

[dts3909]

For simplicity, to force the "ILLEGAL" traffic to HPE's Q3 (802.1p - priotiy = 0), would I set all traffic other than voip and video to Q3  similar to the examples listed below????

VLAN   111

qos priority 0

exit

VLAN   222

qos priority 0

exit

VLAN   333

qos priority 0

exit

Thank you.