07-15-2008 02:07 AM - edited 03-03-2019 10:43 PM
Hi All,
I really want a sanity check as to if I ma going about my issue the right way.
At my HQ I have a MPLS connection to a SP. My remote sites have limited bandwidth. I want to create separate classes for each sites which average to certain speed. I then want inside each average to give voice priority always.
My test config is as follows.
class-map match-any voip
match ip dscp ef
class-map match-any qos_110
match access-group 111
class-map match-any qos_111
match access-group 112
policy-map child_111
class voip
priority 48
class class-default
fair-queue
policy-map child_110
class voip
priority 48
class class-default
fair-queue
policy-map parent
class qos_110
shape average 128000
service-policy child_110
class qos_111
shape average 128000
service-policy child_111
The way I understand it, is that I have average the BW to each site to 128k, and within that BW when there is voice traffic it always gets priority.
As the 'rest' of the traffic, I'm not that concerned, hence the 'class-default' class.
07-15-2008 02:13 AM
Hi,
It looks a bit overly complicated to me,
Basically you want to create a top level policy-map with class class-default, and shape to desired rate.
Secondly configure a class-map and match your voip traffic within, then create a new policy-map and configure LLQ as required, ie, priority 48.
For example
class-map cvoip
match ip dscp ef
policy-map pvoip
class cvoip
priority 48
policy-map ptop
class class-default
shape average 128000
service-policy pvoip
then attach ptop to the interface outgoing...
The logic here is that when and only when the top level policy-map is shaping, ie you are sending more the 128k pps, then it calls the 2nd level polic-map and traffic within the cvoip class gets priority, everthing else gets best effort.
HTH
LR
07-16-2008 12:24 PM
Thanks for that.
However, how do I apply it for several sites based on an ACL, so that each sites gets the same policy (voip 48 priority and shaping at 128)?
Regards
07-15-2008 04:59 AM
If your MPLS provider supports QoS, your policy should be configured to work in conjunction with theirs. (Without any MPLS QoS, a correct QoS policy is difficult to support if you can have remote site to remote site traffic.)
Whether the provider supports QoS or not, you'll still need to address interface congestion on your router.
You'll want to insure your VoIP goes first both at your interace and upon MPLS egress. (Again, the last is difficult to control outside of working with the provider's egress QoS.)
Without MPLS egress QoS and assuming there's no traffic between remote sites, you'll want something like:
(NB: syntax might be incorrect)
class-map match-any qos_110
match access-group 111
class-map match-any qos_111
match access-group 112
class-map match-all voip_110
match ip dscp ef
match class qos_110
class-map match-all voip_111
match ip dscp ef
match class qos_111
policy-map HQ
class voip_110
priority 48
class voip_111
priority 48
class qos_110
shape average 80000
class qos_111
shape average 80000
(if you don't oversubscribe the local interface, this configuration could be used)
class-map match-any voip
match ip dscp ef
class-map match-any qos_110
match access-group 111
class-map match-any qos_111
match access-group 112
policy-map child
class voip
priority 48
class class-default
fair-queue
policy-map parent
class qos_110
shape average 128000
service-policy child
class qos_111
shape average 128000
service-policy child
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