Experimental Physics and
Industrial Control System

NAMESERVER: Channel Access Nameserver

The CA Nameserver is used to provide IP addresses of EPICS process variables (PVs) to Channel Access client programs. Without a nameserver, CA clients broadcast searches for PVs adding to the load of every IOC in the system. With the nameserver in use, broadcasts can be directed only to the nameserver, decreasing the load on the IOCs.

Documentation

The following documents are available. Textual links are to HTML or text documents, other formats are indicated by an icon link.

• CA Nameserver Release Notes (Latest)
  
• CA Nameserver Documentation (still rather old) (August 2022)
  

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• CA Nameserver Release Notes (May 2015)
  
• Nameserver Version 1.2
  by Joan Sage (September 2002)
  

Software Download

The sources for this project are now being managed in the epics-extensions/ca-nameserver project at GitHub.

The following tar files of older releases contain source code only (no binaries). See the GitHub link above for new versions.

• nameserver2_0_0_14 (12 May 2015)
• nameserver2_0_0_12 (27 Oct 2009)
• nameserver2_0_0_11 (20 Sep 2006)

Required Software

The above versions of the CA nameserver use GNU-style regular expressions. More recent GitHub releases can be built to use the Perl Compatible Regular Expression library instead. The chosen library must be built and configured before building the CA nameserver, although both are commonly provided with most Linux distributions.

A version of the GNU regex library that builds as an EPICS Extension module is available below and must be be downloaded and built before the nameserver itself when using the old tar files above.

• gnuregex