Re: EPICS_IOC_LOG_PORT value

["Johnson, Andrew N." <anj@anl.gov>]

Hi Han,

On 10/04/2018 02:45 PM, Jeong Han Lee wrote:
>   The following two files has 'enable' EPICS_IOC_LOG_PORT [1] and
> 'disable' EPICS_IOC_LOG_PORT [2].
> 
>   One enable one is 7004, and the other disable one is 6500. It doesn't
> matter technically, but why not the same value of both?
> 
>   What do you think?

The value 7004 given in configure/CONFIG_ENV is the default value which
gets compiled into libCom.

> [1] configure/CONFIG_ENV
> [2] modules/libcom/src/log/S99logServer@

The S99logServer@ file is a template for a System-V init script that
sites can use to start a log server. When Base gets built the
@INSTALL_BIN@ macro in that template is replaced with the path to the
Base installation, and the result is installed into the bin/<host>
directory as S99logServer. To use this script though the user would
still have to copy the S99.. file into an appropriate directory under
/etc/init.d on the machine that will run the log server, and they should
also make any changes to the other variables in that file as needed by
their installation (usually the EPICS_IOC_LOG_FILE_NAME variable at least).

The commented-out value 6500 that appears for EPICS_IOC_LOG_PORT in the
script is to show that you can override the compiled-in default port
number if you want/need to. Here at the APS we used to run 3 or 4 log
servers, with IOCs from different parts of the machine logging to
different ports (on the same host) and hence to different log-files.

Nowadays it is not necessary to use our log server, and I suggest that
sites use a plugin for one of the many common logging servers now
available such as logstash instead. When enabled the IOC's log client
just opens a TCP socket to the host and sends plain text messages, so
most tcp input plugins will work fine instead.

I can provide a configuration file for logstash that I have experimented
with to anyone who wants it, but I'm sure that most other log servers
would be able to do the same thing.

HTH,

- Andrew

-- 
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