Bradley Smoker PLC-5 user manual Using Domain Name Service

Communicating with Devices on an Ethernet Network 11-15

Using Domain Name Service

DNS allows an Internet Protocol (IP) address in symbolic form to be converted into the equivalent numeric IP address. For the PLC-5 controller, this conversion is a service provided by a remote host on the network.

With this release of Ethernet PLC-5 controllers and release 5.20 or greater of RSLogix programming software, you may enter the symbolic form of the IP address as the IP address in the Message Block.

The Channel Configuration feature in RSLogix5 programming software allows you to configure a primary and secondary DNS server, as well as a Default Domain Name (for example, cle.ab.com).

DNS names consist of a label name and a domain name. When programming the message instruction, you can enter the full label and domain name (for example, Motor1.cle.ab.com) or just the label name (Motor1). The default domain name (cle.ab.com) is appended to the label name.

Label names must start with a letter and can only consist of letters, digits and hyphens.

When a message instruction with a label name is first used, the PLC-5 controller verifies that label name with the name servers. When the IP address is returned, the connection is made. After the connection is made, subsequent message instruction will not require label name verification.

Publication 1785-UM012D-EN-P - July 2005