Unique VLAN configuration in multiple templates

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Unique VLAN configuration in multiple templates

When using Unique subnetting in the VLAN config of a template, is the assigned subnet guaranteed to be unique within the scope of the template or the entire organisation?


We have existing networks that are not bound to a template (yet) that fall within the same range of possible subnets in a new template and I am trying to confirm if there is any risk of duplicating subnets.



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Hello Daniel,


When a template is linked to a site of an organization, the existing configuration before is overwritten to make room for the configuration pushed by the template.


However, when a site is linked to a template, you can modify its configuration without impacting the whole site but the problem is that when you make modifications on the template, once again the existing configuration will be overwritten by it if there is a difference.

Thanks for taking the time to reply, @Thierno .  My question is more about the uniqueness of the VLAN subnets that are assigned.

Kind of a big deal
Kind of a big deal

> subnet guaranteed to be unique within the scope of the template or the entire organisation?


I don't know the answer for sure.


I believe it is only unique to that specific template.


If the subnets are used in AutoVPN, and a duplicate subnet error does occur, you will get an error when clicking saving preventing the config from being used.


So depending on the degree of overlap, you might click "save" most of the time successfully and every now and then it will generate an error.

Thanks, @PhilipDAth .  I guess that is the worst case scenario and that might be manageable in our environment given that we are talking of only c.30 networks already using the same /24 subnet.


Much appreciated.

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In case anyone else finds this useful, Meraki Support pointed me to the Docs where it does state that it is guaranteed to be unique in the Org and not just in networks bound to the template:

"The subnet will be randomly selected based on the address space and subnet mask, but will not use any subnets that have previously been used in the organization."


Don't know how I missed that!

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