[c-nsp] QoS and Router Originated Traffic

[Ivan]

Hi,

I have a requirement to ensure all traffic across certain links have 
particular CoS markings.  Applying QoS polices on the links works but 
doesn't capture router originated traffic - BGP, ARP, IPv6 ND etc.

As a potential solution I have tested using IPv4 and IPv6 PBR to force 
router traffic via lo0

route-map LP permit 10
  set interface Loopback0

ip local policy route-map LP
ipv6 local policy route-map LP

and have set a QoS policy on lo0

interface Loopback0
  service-policy input LOOP0-IN

this sets a qos-group which is matched the outgoing non-loopback 
interface and sets CoS as required.

As far as I can tell it works pretty well but I have a few questions

1) I don't think this works for ARP.  I tried to match protocol arp 
using the loopback0 policy but

router(config-if)#service-policy input LOOP0-IN
  'match protocol arp' is not supported on input service-policy

is there anyway to set the CoS value for ARP traffic from the router, 
ideally only on some interfaces?

2) Is this configuration going to kill my router - maybe I am forcing 
some process switching?

Thanks

Ivan