Layer 2 Fail-over between different service provider

[gnkhan2]

Dear Team, I have setup as per attached diagram. I have two sites that is SITE-1 and SITE-2. The SW1 is Layer switch installed at my SITE-1 and SW2 is the layer 2 switch installed at my SITE-2. I want to configure the fail-over at Layer 2 so that traffic is directly shifted to SP2 in case the primary SP1 path goes down. I have configured two same VLAN 101 from both service provide and configure the port connected with router as an access port at both sites. The ports assign to me by both service provide are configure as trunk port with VLAN allowed 101. SW-1 and SW-2 are under my administration whereas the switches in the middle are of two Service provider network. what i want to achieve is to shift the L2 traffic on 2nd Service provider in case the SP1 goes down. would the STP will help me in this scenario as my switches are not directly connected with each other and i don't know about the configuration of the service provider network. The detail diagram of the network is attached! A quick response/guideline in this regard will be highly appreciated.

[balaji.bandi]

Suggest to Look at IP SLA :

https://networklessons.com/tag/ip-sla/reliable-static-routing-with-ip-sla

[gnkhan2]

Dear,
Thanks for your reply, but IP SLA will not help in this case as this is pure L2 network ( L2 interfaces) and IP SLA work at Layer 3.

[balaji.bandi]

As per the diagram I was in the impression you have different ISP - Provider handover you L2, But you can make it L3 if you like.

If the provider handover to you Pure L2,

If it is L2 here are options :

you can do Port-bundling that can take care of automatic load sharing.

you can also do trunk so one of the Link goes blocking mode as per spanning-tree. (that will automatically unblock mode when the other circuit not reachable)

bear in mind if you are connected to Service provider NTU, your link always up and far end failure can not be detected here.(until you have Dark fibre between sites)

Another alternative option is, make it L3 point to point interface each side, make your IP SLA tracking or routing logic in place for Traffic engineering.

Hope this makes sense?

[gnkhan2]

Hi,
The interfaces cannot be make L3 interfaces as well as the LAG cannot be configure between two ports due to some limitation from service provider network.
what we are facing the main issue is, our switches are connected to Service provider NTU, which always keep UP the interfaces and thus far end failure can not be detected.
this is main issue need to be resolved!

[balaji.bandi]

At the Moment until we have configuration to look i can only suggest for now ws  Have you tried Trunk ?