Azure vMX HA pair - can both be in same VNet?

[Paul2zl]

Hi

If a want a resilient pair of vMXs in Azure can they/should they be in the same Azure VNet and subnet?

On the one hand this page is showing 2 VNets, but there is then another diagram showing them both in the same VNet.

https://documentation.meraki.com/MX/Other_Topics/Deploying_Highly_Available_vMX_in_Azure

Many thanks

Paul

[PhilipDAth]

How would you get Azure to failover the routing from one unit to the other?

[PhilipDAth · Accepted solution]

I haven't seen the guide before.  It uses an Azure function to automate the failover of the static routes.

I don't see why this approach would care if you were using 1 or 2 VNETs.

[Paul2zl]

Yes exactly, that is my thinking, I see no reason from an Azure perspective why they can't be in the same vnet.

With the Azure UDR (dynamically updated by the Azure Function based upon the availability of the primary instance) we would specify the IP address of the active vMX.

It was the first diagram in the guide that was causing me to question this, and think there might be something intrinsic about the vMXs that means that the 2 of them (in an HA pair) couldn't share the same VNet.