Question 103152 in Azure Question posted in
The official documentation to get you started can be found here.

Azure – Virtual network warns about address overlap with itself

Azure warns about the address spaces of one virtual network overlapping with the address space of another (such networks cannot be peered). This makes sense.

However, I am noticing that Azure also warns me about the address space of a virtual network overlapping with itself:

enter image description here

Address space 10.2.0.0/16 overlaps with address space 10.2.0.0/16 of virtual network ‘poboy_vnet’. […]

There is only one poboy_vnet in my subscription.

Is this a bug?

P.S. Not sure but it is possible this only occurs with vnets that are peered with some other vnet.

Edit: Since @Imran mentioned address space overlap between different subnets of poboy_vnet as a possible reason, here is the subnet configuration. As far as I can tell there is no address space overlap:

enter image description here

Tags:

4

Answers


  1. 0

    I tried to reproduce the same in my environment I got the results successfully like below:

    The reason you are seeing this warning is because of virtual network’s address spaces overlap those to another virtual network same address space is defined multiple times within the same virtual network. This may occur if several subnets are sharing the same address space within a single virtual network.

    Each virtual network has a unique address space. If you define the same address space for multiple subnets within a virtual network you will receive a warning that the address space overlaps with itself.

    To resolve this issue, Check the below workarounds:

    If your Address space is overlapping try to remove the subnet like below:

    enter image description here

    In Address space, I have added a new address space and created a subnet with that address space like below:

    enter image description here

    enter image description here

    To peer vnet create another virtual network with default subnet and peering with khan-vnet successfully like below:

    enter image description here

    Login or Signup to reply.
  2. 0

    I am facing the same issue since yesterday. I agree that this warning feels like a bug. None of the address ranges in my vNets are overlapping and even the subnets are correct and non-overlapping.

    Seems like some bug since it started from yesterday and not before that.

    Login or Signup to reply.
  3. 0

    This is a bug and has been resolved. You can navigate to https://ms.portal.azure.com/?feature.canmodifystamps=true&Microsoft_Azure_Network=flight4

    This URL wont perm fix the issue but, if you need to peer a vnet, you can login with that URL temporarily to peer the vnets or manage the vnets until the fix is globally deployed, sometime next week.

    Login or Signup to reply.
  4. 0

    Noticed the same for newly added address space. Then checked for existing Virtual Networks and found that warning is displayed for last address space in every Virtual Network. Seems to be bug.

    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search