Meraki MX 105 High Availability not working

[Shyam1]

Hi ,

We have two links one with /30 subnet mask , other with /19 subnet mask ( static IPs configured on Standalone Firewall WAN Interface ) 

When we tried to configure warm spare between 2 MX105-HW , we faced the following issue.

IP Conflict : Uplink IP address is the same on other device.

After configuring warm spare , both the primary and secondary were in Current Master state.

Kindly help me with how to proceed further, do we need to ask ISP for 2 separate public IP per ISP or with the same /30 & /19 subnet HA can be configured ( note : in /19 ISP - only one IP is able to reach public internet ) 

[ww]

Yes you need 2 or 3 ip's from each isp.

"Ensure that both MXs have their own uplink IP address for dashboard connectivity as described in the Uplink IP Configuration section.

If a virtual IP is being used, an additional IP address is needed, and all three IPs must be in the same subnet."

https://documentation.meraki.com/SASE_and_SD-WAN/MX/Design_and_Configure/Deployment_Guides/MX_Warm_S...

[Shyam1]

Hi,

Thank you for the response . I will check on the same and get back to you. 

Can you please help me with the list of pre-requisites for setting up Warm Spare in 2 nos. of MX105 as Active Passive

[DarrenOC]

As already mentioned by @ww .  You need a /29 from your ISP for HA. One IP per MX and a 3rd as the VIP