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

Question

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

Answer 1

@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

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

Hope this helps.

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

Cheers,

Kapil