I just signed up for SendGrid and I need to add these (top image) SendGrid CNAME records to my Google domain. The issue is that it doesn't tell me what to put into the first field ("@"). If I leave it blank I get an error (see bottom image). Please help.
PS: Adding www as per the Google Domains Help page gives me a naming conflict as there is already an A record with www.
You need to add the CNAME records with the domain you are trying to authenticate removed from the host name. For example, if you are trying to authenticate the domain abc.com, SendGrid will show three CNAME records with host names: emXXXX.abc.com, s1._domainkey.abc.com and s2._domainkey.abc.com. In Google Domains you will need to add three custom resource records of type CNAME with names: emXXXX, s1._domainkey and s2._domainkey. For each of these you must add the value SendGrid provides as the data of the CNAME record. It can take a while for the information to propagate, so verification won't work straight away. Retry after a few hours.
Made this mistake myself with Google domains and realized it few days later (I was waiting for upto 48 hours for CNAME update to propagate as informed by message after you save CNAME record).
Anyway, assuming your google domain is xyz.com and you want to add a CNAME record where someprefix.xyz.com should redirect to somesite.com.
WRONG way of doing this:
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| someprefix.xyz.com | CNAME | 1 | somesite.com | ❌
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RIGHT way of doing this:
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| someprefix | CNAME | 1 | somesite.com | ✅
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It took me a few days to figure out the issue. It's quite misleading based on what SendGrid shows you. Anyway, the solution is simple. When you copy from SendGrid, make sure you delete the name of your domain when you paste it in Google Domains field. For example:
Your domain is ABC.COM From SendGrid you will have:
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| url444.ABC.COM (COPY) | u2225555.cf555.sendgrid.net (COPY) |
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When you go to Google Domains to add a record, you will type: url444 and then you select CNAME from the dropdown menu, leave the default value for TTL to 1, and in the next field you will put whatever SendGrid provided with no deletion. So, in Google you should have:
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| url444.ABC | CNAME | 1 | u2225555.cf555.sendgrid.net |
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Mr.Hunt is correct. The reason for this is because when adding a CNAME record through the domains.google.com platform, it automatically appends your domain name to the end of the host name field, so if you choose the copy option from the SendGrid Domain Authentication page, it will add your domain name in twice. So in short just remove your domain name when pasting into the host name field.