Re: How to know which CA client(IP address) modified a PV

["Shen, Guobao via Tech-talk" <tech-talk at aps.anl.gov>]

The deployment here at APS is exactly what Andrew presented in 2018 as Ralph citated in the [2].

We are using logstash to receive the message, which includes the change info.

One thing to be caution is to configure the IOC not sending every PV changes, for example those PV used in the fast orbit feedback system.

 

Thanks,

Guobao

 

From: Tech-talk <tech-talk-bounces at aps.anl.gov> on behalf of Ralph Lange via Tech-talk <tech-talk at aps.anl.gov>
Date: Tuesday, May 13, 2025 at 2:36 AM
To: EPICS Tech Talk <tech-talk at aps.anl.gov>
Subject: Re: How to know which CA client(IP address) modified a PV

caPutLog is used in a lot of installations, usually with a remote server receiving the messages.

(The behaviour that Guobao described is unknown to me.)

 

Traditionally, iocLogServer would be used for that, most often on a different port to keep the caPut logs separate from the regular IOC logs.

Note that iocLogServer is deprecated, and we intend to drop it at some point in the future. No worries: this will not happen anytime soon.

Compatible log stash configurations can be used as a replacement without changing the IOC side. For more information, look at this issue ticket for the initial discussion [1] and Andrew's slides at the EPICS Collaboration Meeting in 2018 [2].

 

Cheers,
~Ralph

 

[1] https://bugs.launchpad.net/epics-base/+bug/1786966

[2] https://events01.synchrotron.org.au/event/85/contributions/2601/