IP PRECEDENCE

[Federico Olivieri]

Hi all,

I have the following conf on my router:

class-map match-all NBAR_NTP
match protocol ntp
class-map match-all NBAR_DNS
match protocol dns

policy-map DNS_PREC
class NBAR_DNS
set ip precedence 4
class NBAR_NTP
set ip precedence 3

The policy is applied to the interface where the server is connected:

interface FastEthernet0
no ip address
load-interval 30
service-policy input DNS_PREC
hold-queue 1000 in
hold-queue 1000 out

But when I check the stats no one packet seems to be marked by the policy-map

887VA#show policy-map interface fastEthernet 0
FastEthernet0

Service-policy input: DNS_PREC

Class-map: NBAR_DNS (match-all)
0 packets, 0 bytes
30 second offered rate 0000 bps, drop rate 0000 bps
Match: protocol dns
QoS Set
precedence 4
Packets marked 0

I' m not expert in QoS. What is wrong with my configuration? What I' m trying to achieve is to give priority to the DNS traffic and NTP traffic. Is it the right procedure to do it?

Thanks

[Federico Olivieri]

Ok,

Mybe I have figured out by myself.

My router is cisco 887 and the 4 fastethernet are under vlan 1 interface. If I apply the policy to the interface vlan, I can see the packet get marked.

Vlan1

Service-policy input: DNS_PREC

Class-map: NBAR_DNS (match-all)
981 packets, 94954 bytes
5 minute offered rate 2000 bps, drop rate 0000 bps
Match: protocol dns
QoS Set
precedence 4
Packets marked 981

Now, one question remain: is it the right conf for what I'm looking for?

The setup is the following:

ADSL---CISCO887---FIREWALL---SERVER

The DNS and NTP traffic is biderectional. The policy that I have applied is it enough in order to prioritize the traffic?

Thanks