Okay which do you want ie you say you want one as backup and then you talk about load sharing equal cost paths.
If they are both Cisco routers you can use EIGRP and add a delay to the interfaces of the backup link on both routers so the other link is preferred. If it is just these two routers then even with the delay the backup link should be seen as a feasible successor so failover will be very quick.
Perhaps you could explain a bit more about your topology. Is it literally one network at each site connected by a single router with two links on each router ?
Yes, by default it load balances across equal cost paths.
But you are using HSRP on the router so it wont see two equal cost paths anyway ie. all traffic goes to the HSRP active router so it will smply use it's own link. So you could simply match up the HSRP active on both sides so that the same link was used for traffic both ways.
If those are serial links you could also track the state of the serial link at both ends and failover if the serial link went down.
The only failure scenario that would cause a problem would be if the LAN interface of the HSRP active router failed. Then it will failover but the other end does not because it's serial link connection is stll up. So it sends traffic to the router with the failed interfaces.
To get round that you could always use IP SLA tracking or maybe EEM to shut the serial interface if the LAN interface fails and then the other end would failover as well.
Can you clarify whether those links are serial point to point links ?
I am just not sure what a routing protocol gives you in this instance.
It depends where the failure is. If they are point to point links then if one end fails the other end should go down as well. However if these are being provisoned by a provider they may well appear point to point but they may go through provider switches in which case if one end fails the other might still think it is up.
The only way to test if to shut one end down and see if the other end goes down as well.
Lets assume they do behave like that and you are using HSRP. You are also tracking within HSRP the status of the point to point link -
1) if the link itself fails then both routers should see the WAN interface go down and because you are tracking with HSRP both router failover to the othe HSRP router so it all works
2) if the WAN interface on either router fails the other router's WAN interface should go down and again because of HSRP tracking both routers failover.
3) if either active router at each end of the link fails then again the other router's WAN interface should go down and both routers failover.
4) if the LAN interface on one of the active routers fails then it fails over to the other router. But the active router at the other end does not failover because it's WAN link is still up because it was the LAN interface that failed on the router not the WAN interface.
All of the above as i say depends on whether those links act as true point to point links. If they don't then you definitel can't rely on HSRP with tracking for any failover.
So it depends. And if you wanted to be sure of failing over in all scenarios then you may need additional configuration.
Hi everyone, I would like to thank you in advance for any help you can provide a newcomer like myself!
Im studying the 100-105 book by Odom and am currently on the topic of Port security. I purchased a used 2960 and I'm trying to follow a...
While deploying a number of 18xx/2802/3802 model access points (APs), which run AP-COS as their operating platform. It can be observed on some occasions that while many of their access points were able to join the fabric WLC withou...
I am going to design and build an LAN network under a tunnel underground with long distance between the switches.
I will have 2 Catalyst switches and 8 Industrial IE3000, and they will be connected with fiber.
For now I am planning on use Layer-2 s...