I have two wireless backhauls that I would like to set up, using the faster of the two as the primary link and allow the RB450 to failover to the slower link if/when the primary link fails. I do not want to load balance across the two links. I envision an active/standby relationship between the two WAN links. I’ve seen a few topics that are close to this but would appreciate specific examples.
Thanks!
Use OSPF? http://wiki.mikrotik.com/wiki/OSPF
Add the two OSPF network subnets for the two links changing x.y.z.0/24 and x.y.w.0/24 for the real IP and “/ values” used on your two links
/routing ospf network
add network=x.y.z.0/24 area=backbone
add network=x.y.w.0/24 area=backbone
By default, OSPF interfaces get a cost value of 10. Therefore if we choose a higher cost when adding the backup interface, the traffic will to go over the other one by default, as it has a lower cost of 10.
Assuming the router at each side has the slower (backup) link on wan2 and the faster link on wan1 add
/routing ospf interface add interface=wan2 cost=100
(wan1 will get dynamically added with a cost of 10 by default so it is not necessary to add this manually)
When the primary link fails, traffic will be routed over the slower backup link automatically.
Is that the sort of thing you were looking for?
One thing about using OSPF is the the hello timers and the router dead interval. The hello timer is set for 10 and the router dead timer is set for 40 sec. All parameters must be set the same on all routers. The router dead timer declares a neighbor dead at said interval (40 sec). You can lower this time or even the the hello timers if you want a fast trigger for real time applications such as voip. Another approach is to use the netwatch utility (see manual version 2.9) and have a trigger which activates a script which changes the default route.
-Brian