Name

SRV (service location) —

Textual representation:

                     owner ttl class SRV priority weight port target

Example:

_http._tcp.movie.edu.  IN  SRV 1 2 80 www.fx.movie.edu.
                       IN  SRV 1 1 8080 www1.fx.movie.edu.

Binary representation:

SRV type code: 33
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                   PRIORITY                    |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                    WEIGHT                     |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    |                     PORT                      |
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    /                    TARGET                     /
    /                                               /
    +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+

where:

PRIORITY

As for MX, the priority of this target host. A client MUST attempt to contact the target host with the lowest-numbered priority it can reach; target hosts with the same priority SHOULD be tried in pseudorandom order. The range is 0-65535.

WEIGHT

Load balancing mechanism. When selecting a target host among those that have the same priority, the chance of trying this one first SHOULD be proportional to its weight. The range of this number is 1-65535. Domain administrators are urged to use Weight 0 when there isn’t any load balancing to do, to make the RR easier to read for humans (less noisy).

PORT

The port on this target host of this service. The range is 0-65535. This is often as specified in Assigned Numbers but need not be.

TARGET

As for MX, the domain name of the target host. There MUST be one or more A records for this name. Implementors are urged, but not required, to return the A record(s) in the Additional Data section. Name compression ...

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