How do I add both a CNAME and an A record to Route 53 to use my blog with Pressable?

Question

I'm also aware that I'm unable to have a CNAME as the domains root under the ruling 3.6.2 of RFC 1034 as in this post.

I'm trying to add an external blog hosting service. So I have my domain at www.example.com. I want to add a sub-domain called: blog.example.com

The external blog hosting service (Pressable) asks me to add an A record, no problem but they also want a CNAME: blah.openhostingservice.com.

Of course trying to do that just yields this in Route 53:

RRSet of type CNAME with DNS name blog.example.com. is not permitted as it conflicts with other records with the same DNS name in zone example.com.

How can I add this CNAME?

Update: The message from Pressable

To launch your site you need to do the following:

1. Point your domain to pressable

Want to MANAGE YOUR OWN domain settings?

Point your A record to xx.xx.xx.xx

AND

Change your CNAME www to yyy.xyz.com

2. Add the domain you want to use below

Where xx.xx.xx.xx is the IP and yyy.xyz.com is the url they provide. Step 2 is just the spot to let them know the sub-domain I selected.

Solution

The issue here is that you are trying to create two separate DNS entries for the same FQDN. From reading your question several times what I gather is that the instructions you are reviewing are working on the basis that both the zone apex (domain.com) and the standard DNS (www.domain.com) both need to connect to the Blog service. In this case you would create an A record at the zone apex with the IP address they provide and a CNAME record for www to the zone apex.

IE:

    IN    A        XXX.XXX.XXX.XXX
www IN    CNAME    domain.com

What you are trying to do though is direct blog.example.com to the third party provider while keeping the zone apex pointed to your own server so what you could here would be...

       IN    A        {YOUR IP}
www    IN    CNAME    domain.com
blog   IN    CNAME    provider.domain-name..com

Comments

[Steve]

If blog.domain.com has an A record, try deleting that first.

[closetnoc]

I have read this a few times and it does not make sense to me. What is the A record for specifically and what is the CNAME for specifically. I think there was a disconnect in the translation- perhaps between you and the host? You may want to double check with their tech support. If they sent an e-mail, then perhaps you can cut and paste that portion in the question. This should be a simple thing and easy to resolve. Cheers!!

[user2800204]

@Steve I can add CNAME if I remove A first but then I can't add A after.

[user2800204]

@closetnoc - updated with message. Their tech support is not helpful.

[closetnoc]

Let me get clear this up some. I am assuming that your domain example.com you want pointing to your server to show your (existing) website and that blog.example.com will be this blog app. If this is the case, all you needed to do is add a CNAME for blog.example.com pointing to blah.openhostingservice.com which the blog company would have set-up for you already. Is my understanding of your situation correct? If so, then there is no need for any A record that I can see.

[closetnoc]

If they are expecting you to add an A record for blah.openhostingservice.com, then that would be silly since it is their own domain. But if that is what they meant, then I get it and perhaps can help.

[user2800204]

@closetnoc You are right in your assumption, example.com is my existing site and blog.example.com is the pressable blog app I'm trying to add. I'm just going by what they say. They want me to add the A record AND the CNAME at least according to the setup doc. Adding just the CNAME is no problem or adding just the A record is fine but I can't add both in Route 53. So are you suggesting that the A record is unnecessary? Why would they say I need both?

[closetnoc]

Is the A record for A record for blah.openhostingservice.com? Or is the A record for blog.example.com? If it is for blog.example.com and the CNAME is for blog.example.com, that is an impossible task. You only need one and can only have one. I suggest the CNAME and not the A record. The CNAME covers many sins and is more flexible.

[user2800204]

@closetnoc I should've clued in that blah.openhostingservice.com resolves to the A record IP they provide. I guess I don't understand why they want both added?

[closetnoc]

If blah.openhostingservice.com already resolves to an IP address, you do not need to add an A record. Just a CNAME for blog.example.com pointing to blah.openhostingservice.com.