R(config-oer-mc)# {delay|loss|jitter|mos|unreachable} [threshold MIN| relative PERCENTAGE] ...
R(config-oer-map)# set {delay|loss|jitter|mos|unreachable} [threshold MIN| relative PERCENTAGE] ...
The router will try to find a new exit interface for a Traffic Class if it goes OOPOLICY, but also after a fixed period, regardless of the status. This timer is disabled by default but it can be set with:
R(config-oer-mc)# period SEC
R(config-oer-map)# set period SEC
When a Traffic Class is moved to a new exit, it will not be changed again until a holddown timer expires. This timer is configured with:
R(config-oer-mc)# holddown SEC
R(config-oer-map)# set holddown SEC
Once a Traffic Class becomes OOPOLICY it has to wait a backoff time before beeing moved to an INPOLICY state. This backoff time starts at the MIN value and increases with STEP value for each time the MC tries to move it INPOLICY, but fails. It can't grow more than MAX.
R(config-oer-mc)# backoff MIN MAX STEP
! Default: MIN=300, MAX=3000, STEP=300
R(config-oer-map)# backoff MIN MAX STEP
! Default: MIN=300, MAX=3000, STEP=300
When chosing an INPOLICY exit there may be multiple available choices. The MC will chose it based on the order of the resolvers (based on priority. Lowest goes first). Priority 0 is always reachability, so traffic will not be blackholed. To define the order of the resolvers, use:
R(config-oer-mc)# resolve RESOLVER priority PRI [variance VAR]
! cost Specify PfR cost policy resolver settings
! delay Specify PfR delay policy resolver setting
! jitter Specify PfR jitter policy resolver settings
! loss Specify PfR loss policy resolver settings
! mos Specify PfR MOS policy resolver settings
! range Specify PfR range policy resolver settings
! utilization Specify PfR utilization policy resolver settings
R(config-oer-map)# set resolve RESOLVER priority PRI [variance VAR]
By default, after Reachability (priority 0), the MC uses Delay (priority 11) and utilization (priority 12) to solve the problem. The Variance value is used to consider equal multiple values within the same variance. (E.g. Delay values of 300 and 320 are considered equal if the variance is at least 20).
Then, if there are multiple exits that would move the Traffic Class INPOLICY, the router can select the best exit, or any of the good enough exits, based on this command:
R(config-oer-mc)# mode select-exit {good|best}
R(config-oer-map)# select-exit {good|best}
When selecting the exit, routers can use by default any external interface. But for some types of traffic, you can select the exit interface on a subgroup of the external interface. Remember that each external interface can be part of up to 3 LINK-GROUPS. If GROUP1 is not available, then GROUP2 can be used.
R(config-oer-map)# set link-group GROUP1 [fallback GROUP2]
For some types of traffic you can select a more static exit strategy:
R(config-oer-map)# set next-hop NEXT-HOP-IP
To drop traffic, just use:
R(config-oer-map)# set interface Null0