Load Balancing With 2 MXs and 2 Internet Connections

[antricc]

From what I can tell, load balancing between two internet connection is only supported when both uplinks are connected to a single MX. I am in a spot where the internet funding for my two internet connections relies on them being used concurrently. I am trying to avoid a single point of failure and would like to have two MXs each with a single internet connection that load balance my internet traffic, I think this would be more along the lines of GLBP but meraki seems to take a VRRP approach which does not allow for load balancing. Is there a way to implement load balancing between two MXs?? Any suggestions or questions are appreciated!

[RaphaelL]

Hi ,

Is there a way to implement load balancing between two MXs??  Not to my knowledge. VRRP ( warm spare ) uses an Primary and a Secondary MX : https://documentation.meraki.com/MX/Deployment_Guides/MX_Warm_Spare_-_High_Availability_Pair

This week RyanMiles provided us with a great design to include dual WAN and dual MXs. Give it a look : https://community.meraki.com/t5/Security-SD-WAN/How-to-turn-MS120-into-WAN-breakout-for-2-ISPs-and-2...

https://docs.google.com/presentation/d/1xsb8imtUFjN13so86kIZ04IR9f6WEKdbpUrYVON64Zg/edit?usp=sharing 

Hope that helps !

[antricc]

Thanks for the reply! I am far from a network engineer but have been tasked with configuring a campus to support 4 spoke locations from the internet connections terminating at our hub location. I may be overthinking the redundancy of it all but would really love to avoid any outages while staying within budget. I will attach a quick topology I drafted up to see if anyone notices any oversights on my part, the topologies of the spoke locations are not detailed or finalized. Keep in mind that we simply do not have the budget to implement redundant aggregation switches.  

[cmr]

We use MS355s as a core rather than using the MS410.  Could you not get an extra MS350 instead of the 410 and create a stack of three switches?  This will give you all SFP+ ports rather than the 1Gb only SFP ports of the 410.

[antricc]

I like this idea but should have mentioned that I would eventually like to see redundant or aggregated links to each branch since the fiber will already be there, this would be a minimum of 12sfp ports in the core. I might be wrong but I think a stack of 3 350s would still have less switching capacity than one 425.

Do you think having the redundancy at the core while still having a single point of failure due to my MX would be my best route or would you say having the single MX defeats the purpose of the 350 stack? 

[cmr]

A redundant core is crucial to any deployment as internet traffic will only be some of your traffic.  I'd go with redundant both and are you looking at an MS410 (diagram), or MS425 (post above)?  For the cost of an MS425 you should be able to get an MS350 and an MX250...

[antricc]

I did mention the 425 but am thinking it may be a little overkill for my application. What do you think about this...

I am wondering if 2 MS410-16 would be the best option for the core layer. I already have 2 of each MX250 and MS350, 250, 225 in my MDF with most ports on the MS's already taken up. I would create three stacks from each model MS to serve the access layer with redundant and possibly aggregated 1g links to each MS410. The remaining 4 sfp+ will connect my branch locations.

The redundant MX is something I am still unsure how to implement while keeping both internet connections load balancing. Is it possible to run a spare MX with no active uplinks so in case of a failure I could quickly swap the cables from one MX to the other? I can't afford the extra circuit to keep internet access to both MXs which seems to be my only option if I am required to load balance my two existing internet connections.

[cmr · Accepted solution]

Personally I'd add to the stack of MS350s as by using MS410s you are reducing capacity from 10Gb to 1Gb.  If you don't need many more RJ-45 ports then get the 24 port models as they still have the 4x SFP+ ports per switch.

Our main DC has a stack of 4x MS355-24X switches as it was cheaper than 2x MS425 and 2x MS225.  We only needed 16x SFP+ ports, so the option was open to us.  If you need more that 16x SFP(+) ports then the MS410/425 would be a good solution.

[antricc]

I will be needing the extra SFP in the main stack, two MS-410-16 will do the trick as I won't be needing the extra SFP+. Thanks for all the feedback!