The comparison A record vs AAAA record is the old DNS record for domain name resolving against the new one. Their main difference is the IP addresses that they use. The A record uses an IPv4, and the AAAA record uses an IPv6 address.
Learn additional information about the AAAA record
What is an A record?
The A record is one of the first-ever DNS records. Its purpose is to link domain names to their IPv4 address. You need to create an A record inside your Master Forward Zone. Without this record (or AAAA record), your domain name could not be resolved, and your visitors can’t be directed to the right location.
You need to put one A record if your website is available only on one IPv4 address or multiple if your site has multiple addresses (for example, if you have a CDN).
The content of an A record:
- Host: Put your domain name/hostname here.
- Type: A.
- Points to: Put the IPv4 of your server.
- TTL: chose the time value for this DNS record.
What is an AAAA record?
The AAAA record is a DNS record that resolves a domain name/hostname to an IPv6 address. It is newer than the A record, and eventually, it will totally replace it. Until then, you will need to put AAAA records alongside the A records.
The IPv6 offers a lot more addresses and extra features, so it is worth to start using it today.
Just like the A record, the AAAA record’s place is inside the Master Forward Zone. You need it to connect your domain name to your server’s IPv6 address.
You need to add only one AAAA record if your website is available only on a single IPv6 address or more if your site has multiple addresses (for example, if you have a CDN).
The content of an AAAA record:
- Host: Put your domain name/hostname here.
- Type: A.
- Points to: Put the IPv6 of your server.
- TTL: chose the time value for this DNS record.
A record vs AAAA record
Both the A and the AAAA record resolve domain names to IP addresses, but in the first case, the A record directs to an IPv4 address, and in the second case, the AAAA record leads to an IPv6 address.
The IPv6 addresses are 128-bit addresses, and there are far more available than the 32-bit addresses of the A record. The IPv6 exist since 1995 as an idea and was officially introduced in 2017. Its adoption is slow, but eventually, it will be the feature. Probably it will stay for a really long time since there is no potential problem of running out of IPv6 addresses.
The A and the AAAA records can exist together in the same zone. It is not a problem.
One big problem with the broader adoption of the newer AAAA record is that there are still plenty of old DNS resolvers that can’t work with it. Until all that old equipment is replaced, you can’t completely rely on AAAA records only.
Conclusion
A record vs AAAA record should clearly show that the AAAA record is superior, but…
It has been a long time since the IPv4 addresses are running out, but somehow it is still very much present in tech. The newer AAAA records are ready to replace the older DNS records fully, but for now, they are used just alongside the main A records.