Difference Between cisco SLA,PBR and VRF

[Kolanjiyappan Kaliyamoorthy]

Difference Between cisco SLA,PBR and VRF?

Which is best method for fail over concept in the above three.

[Mark Malone]

vrf is not really for failover its for an isolated routing table for MPLS to segregate customers from each other on PE routers , also used on mgmt. interfaces to segregate the mgmt. traffic from prod

ip sla and pbr work best together for failover

the best method is the one that's works for you in your design and what your trying to achieve with these features

[Julio E. Moisa]

Hi

SLA is a method to analize IP Services, it can be used to track the stability of a link or host, I often have used it along with scripts (EEM) to create automatic failover. 

PBR is used for different tasks like: manipulate traffic based in policies, to match/set metrics/set next-hops/tag traffic, etc. 

VRF is a method to create virtual instances, it will create separate different routing tables than the global table. Basically you can have several same networks under different VRF and they will never create an overlap.  Not used for failover.

Now the option for failover is: SLA. It will work along with a track and if you want to create an automatic failover you could include an EEM to create a script and trigger it when an event occurrences.  

Hope it is useful

:-)

[Joseph W. Doherty · Accepted solution]

Which is best method for fail over concept in the above three.

SLA can sometimes be used for detection of a failure although it's really a performance measurement technology.

PBR is an advanced form of static routing, which can be configured for "fail over".

VRF is sort of the L3 equivalent of L2 VLAN, doesn't really have much to due with "fail over".

Of the three, I would perhaps rate PBR as the "best" as you can define what to do for failure.  I would rate SLA as number two because, as noted above, it might be used to detect a failure.

As Mark also notes, VRF doesn't have much to due with fail overs.