This article discusses type SRV and NAPTR DNS records in detail. For a general guide to DNS records and their settings in the customer administration panel, see the article DNS – Domain Records.

In this article, you will learn:

• What is the SRV record for
• How to enter SRV type records correctly
• Examples of SRV type records
• How the NAPTR type record works
• Frequently asked questions

The Service record (SRV) is used to specify information about the host’s available services. These services commonly include, for example, XMPP (instant messaging protocol), SIP (signaling protocol in Internet telephony), or LDAP (a protocol for storing and accessing data on a directory server).

An SRV record type cannot be used to specify a port on which a service is running that does not commonly support this record type.

For example, if you want to run a website (HTTP or HTTPS protocol) on a port other than the normal one, you must set this up on the server. You cannot set this port in an type A, AAAA, or SRV record.

For general instructions on setting up DNS records in the customer administration panel, see the article DNS – Domain Records.

If the domain uses another provider’s DNS servers, automatic or manual changes to WEDOS records will not affect its behavior.

SRV type records tend to have a specific form of name and data.

The symbolic name of an SRV record usually takes the form _sluzba._protokol, such as _sip._udp. 

Add any subdomain to the end of this symbolic name, for example _ldap._tcp.subdom. 

SRV record data consists of the following parts:

1. Priority: a positive integer specifying which record will be evaluated first (the one with the lowest number); the system evaluates other records only in case of unavailability of the high priority service.
2. Weight: relative weight for records with the same priority, used to distribute load.
3. Port: The TCP or UDP port on which the service listens.
4. Target: Hostname of the server providing the service.

Follow these rules when entering an SRV type record:

• Assign the lowest priority number but the highest weight to the master server.
• Enter the hostname in the form of a domain, not an IP address.

A generic SRV record uses this template:

Name              TTL    Typ  Data
(symbolic name)   300    SRV  (priority) (weight) (port) (hostname)

Example: SRV record for SIP over TCP on port 5060 with destination tel.wds-test.eu.

The Name Authority Pointer record (NAPTR) is often used in combination with SRV records, most commonly for Internet telephony needs to map SIP. When entering it, follow the instructions of the service provider.

Question: How do I get DNS to point HTTP to a port other than 80 (or 443 for HTTPS)?
Answer: You cannot arrange this setting in DNS, you have to set it on the web server itself.