Error on trying to add an alias record set: Failed to create record set '@'. Error: Maximum number of aliases to single target reached

DC Dweller 1 Reputation point
2023-10-08T01:21:07.0533333+00:00

Hi there,

In my Azure account, I have a virtual machine, and Public IP address and a number of DNS zones. I was planning to host about 20 web sites on this VM and already have about 10 up and running. Today I tried to create yet another DNS zone for yet another domain, and while trying to add a new alias record set for this domain, I got the following error:

Failed to create record set '@'. Error: Maximum number of aliases to single target reached

According to the documentation, this limit is 20. What should I do? Since my domains require two record sets each (apex and www) does this mean I can only host 10 web sites? This does not make sense at all.

Thanks in advance.

-- Peter

Azure DNS
Azure DNS
An Azure service that enables hosting Domain Name System (DNS) domains in Azure.
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  1. KapilAnanth-MSFT 36,396 Reputation points Microsoft Employee
    2023-10-09T05:27:29.8033333+00:00

    @DC Dweller

    Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.

    I understand that you are reaching the limits with Azure Public DNS Zone.

    Per your verbatim,

    • You have 10 existing Zones.
    • In each zone, you have created a couple of DNS record sets (one "@" and one "www")
      • Both of these record sets are created as "Alias Record Set" with target set as "Azure Resource"
    • So, in total, you now have 20 "Alias Record Set" pointing to the same "Azure Resource" (Public IP Address)

    So, I believe the limit has been met as documented here : Azure DNS limits

    User's image

    I see two workarounds for this.

    #1 If you are using a Standard Public IP

    • In this case, the IP address will not change
      • As Standard SKU IPs are always Static.
    • So, instead of using a "Alias Record Set", you can directly use the IP Address of the Standard Public IP.
    • You can leave the "domain.com" as it is to point to the "Alias Record Set" but change the "www.domain.com" to point to the Public IP Address of the VM.

    #2 For the FQDN, "www.domain.com" - Create a CNAME to "domain.com"

    i.e,

    • apex domain : User's image
    • "www" sub domain : User's image
    • This should automatically take care of any IP Changes as you are not explicitly specifying the IP anywhere unlike #1.
    • Using Dig interface :
      • User's image

    Hope this helps.

    Please let us know if you need more info on this.

    Cheers,

    Kapil

    1 person found this answer helpful.