MS250 warm spare

[RichardM]

Hello,

I am trying to configre a redundant core for my environment. I know i can use warm spare to create a redundant Gateway.

But is this also possible if i have 2 stacks? If not, any idea what would be the best config to build? The switches are located in 2 buildings, which are reachable via a fibre connection. 1 stack per building.

Thanks in advance

[Adam]

Being in two separate buildings or in the same rack shouldn't make a difference if they are connected via fiber.  Are the two stacks actively used or is one truly a backup?  If the secondary stack is truly a backup then I'd think the warm spare option would work fine.  Basically the downstream stacks just uplink to the MX bundle and whichever MX is active is the one that will route the traffic.  

[PhilipDAth]

My first choice would me to try and connect each MX directly to each stack (so they are dual connected).  This may require running additional cabling.

My second choice would be to direct connect each MX, which may require an additional cable.

My last choice would be to dual connect each MX to a single stack.

Don't forget the WAN ports on each MX need to connect to the same upstream - otherwise how can it fail over.

[ww]

not sure, but I think the question is or vrrp option is possible on a L3 enabled switch stack.?

[RichardM]

I am not sure where my firewalls came into this story, but ok 🙂

My situation: two buildings, Buidling A and buidling B. In both buidlings i have a stack of MS250. they are connected through a dual fibre connection.

What i hoped to do was to use VRRP (warm spare) to create a situation where i have a virtual IP for both stacks, which i would use as default gateway for my clients. But it seems it is no possible to do this with a stack. only with single switches.

[PhilipDAth]

You can run VRRP between switches that support it (I think MS250 and above) - however you can not run it between stacks.

[RichardM]

yeah.. so it seems. But how to build a fully redundant network with 4 switches at 2 sites? cant stack, couse than cant use warm spare. if i dont stack, can use warm spare, but only can use 2 switches.. so there will be site redundancy, but not switch redundancy..

choices.. choices...

[PhilipDAth]

Meraki can do N+1 redundancy.  What you are requesting is N+3.  You'll need to use Cisco Enterprise products if you really want N+3 redundancy.