I have several sites connected with each other by the ISP. Each site has a 10Mbps FastEthernet port pointing to the ISP cloud. I have GRE tunnels from one site to each other with OSPF running inside.
I'd like to implement QoS , the question is what are the best practices to do it.
I was thinking about the following config.
class-map match-any REALTIME
match ip precedence 5
match ip dscp ef
class-map match-all MANAGEMENT
match ip precedence 6
class-map match-all CRITICAL_DATA
match ip precedence 4
shape average 10000000
service-policy out 10Mbps
The same policies will be applied to each site.
Assuming that markings are copied from the IP header to the GRE header, any voice traffic in any tunnel should get its priority.
But I have the following questions:
Do I need the 10Mbps shaper in the parent policy?
(Traffic is rate-limited on the ISP side, are there any positive impacts of shaping on my outisde interface?)
What about routing protocols updates and tunnel keepalives? Do I need to assign them their own class, perhaps there are some default markings for them?