DNS record types explained: A, AAAA, CNAME, MX, TXT and more
A plain-English guide to the DNS record types you can manage in the NetOz Portal, with examples for websites, email, SPF, DKIM, DMARC, SRV and CAA records.
On this page
DNS records tell the internet where to find the services for your domain: which server hosts your website, where to deliver your email and which providers are allowed to act for you. When NetOz hosts your DNS, you manage these records in the DNS zones area of the NetOz Portal.
This guide explains each record type the portal supports, when to use it and what a typical value looks like. The examples use example.com and documentation IP addresses. Replace them with your own.
How a DNS record is put together
Every record has four main parts:
| Part | What it means | Example |
|---|---|---|
| Name | The hostname the record applies to. @ means the domain itself. | www |
| Type | The kind of record. | A |
| Value | The answer returned for that name and type. | 203.0.113.5 |
| TTL | How long, in seconds, resolvers may cache the answer. | 3600 |
TTL tip: if you are about to change a record, such as moving your website to a new server, lower its TTL a day or so beforehand. Resolvers then pick up the change faster. Raise it again once the change is done.
A record
Points a hostname to an IPv4 address. This is the most common record. It is used for websites and any server you reach by name.
@ A 203.0.113.5
www A 203.0.113.5
Use an A record for the root of your domain (@), because a CNAME is not allowed there.
AAAA record
Points a hostname to an IPv6 address. It works like an A record, but for IPv6. Many servers have both, and devices pick whichever they can use.
@ AAAA 2001:db8::1
CNAME record
Makes one hostname an alias of another hostname. Resolvers follow the alias and use the target's records.
www CNAME example.com.
shop CNAME stores.example-provider.com.
CNAMEs are useful when a provider gives you a hostname rather than an IP address, because the provider can change their IP addresses without you updating anything.
Rules to remember:
- A
CNAMEcannot be used at the root of a zone (@). UseAorAAAAthere instead. - A name that has a
CNAMEcannot have any other records.
MX record
Tells other mail servers where to deliver email for your domain. Each MX record has a priority. Lower numbers are tried first.
@ MX 10 mail.example.com.
@ MX 20 backup-mail.example.com.
A common convention is 10 for the primary mail server and 20 for a backup. The value must be a hostname, not an IP address, and that hostname needs its own A or AAAA record.
If your email is hosted with a provider such as Microsoft 365 or Google Workspace, use the exact MX values they give you.
TXT record
Holds free-form text. TXT records do many jobs, most of them related to email security and proving domain ownership. Values that contain spaces should be enclosed in quotes.
SPF
SPF lists the servers allowed to send email for your domain. A domain should have only one SPF record.
@ TXT "v=spf1 include:_spf.example.com -all"
Our free SPF record builder and SPF validator can help you get it right.
DKIM
DKIM publishes a public key that receiving servers use to check your email's signature. Your email provider gives you the name, often something like selector._domainkey, and the value.
DMARC
DMARC tells receiving servers what to do with email that fails SPF and DKIM checks, and where to send reports.
_dmarc TXT "v=DMARC1; p=quarantine; rua=mailto:dmarc@example.com"
Verification
Services such as Microsoft 365, Google and many SaaS tools ask you to add a TXT record containing a token to prove you own the domain.
SPF record type
A legacy record type for SPF. Modern SPF is published as a TXT record, as shown above. The SPF type is available in the portal for compatibility only. If you are creating a new SPF policy, use TXT.
NS record
Delegates a subdomain to other nameservers. The NS records at the root of your zone list the NetOz nameservers and should be left alone. You only add your own NS records when you want a different DNS provider to run a subdomain.
dev NS ns1.other-provider.com.
dev NS ns2.other-provider.com.
To move your whole domain to NetOz, see Point your domain to NetOz nameservers.
SRV record
Advertises where a specific service runs, including its port. SRV records are used by chat, VoIP, calendar and autodiscovery services. In the NetOz Portal, the priority is entered separately and the value takes the form weight port target.
_sip._tcp SRV priority 10 value: 10 443 svc.example.com.
Lower priority values are tried first. Among records with the same priority, weight decides how traffic is shared. Your service provider will tell you exactly what to enter.
CAA record
Restricts which certificate authorities may issue SSL/TLS certificates for your domain. The value takes the form flags tag value.
@ CAA 0 issue "letsencrypt.org"
If you add CAA records, include every certificate authority you use. Otherwise certificate renewals from any authority that is not listed will fail.
PTR record
Maps an IP address back to a hostname (reverse DNS). PTR records only work in reverse-lookup zones, which are controlled by whoever owns the IP address range. For a server's reverse DNS, which matters for sending email, ask the provider of the IP address. If that is NetOz, contact our support team.
SOA record
Every zone starts with a Start of Authority record that lists the primary nameserver, the zone contact and timing values. For NetOz zones the primary nameserver is ns1.netoz.au and the contact is hostmaster.netoz.au. NetOz manages the SOA record for you.
Checking your records
After making a change, use our free DNS lookup to see what your nameservers return, or the DNS propagation checker to see whether resolvers have caught up. For email records, the MX lookup is a quick check.
Next steps
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