Experimental Physics and
Industrial Control System

"Jeff Hill" <[email protected]> · Fri, 14 Nov 2003 14:02:38 -0700

> Thinking about the future of EPICS,
> some items on my wish list are:
> 
> [1] A tracing mechanism in to find
> out which host/user last modified this PV.
> Yes, that will take additional memory.
> When trying to locate some aberrant client,
> this is most valuable.  Also, useful when
> trying to identify which user thought
> we had a new d-spacing in our monochromator
> (for example).

There is a new interface in R3.14 which allows site specific put logging to
be implemented in the IOC.

> 
> [2] An EPICS "ping" command or something that
> a sysAdmin could use to identify all the EPICS
> IOCs within a subnet.  Maybe there is already
> documentation on how to do this by probing
> a certain port or some other elegant method.

As Andrew mentioned, there is a tool in R3.14 called casw which prints a
message whenever a server beacon anomaly is detected, and this tool could be
modified to run for a specified time and then print a list of all server
beacons that were detected including there IP address and port number.

> 
> [3] Building upon [2] above, a client request
> for a list of all the PVs offered by a
> chosen EPICS IOC.  This would be a list
> just like the "dbl" command from the IOC shell.
> Why is this useful?  It could be used to answer
> the question "Where is this PV?" (Maybe this, too,
> is already available from the low level C calls.
> Maybe I should take the EPICS course.)

We could certainly easily write a "pvPing" command which prints the address
and port of the server that has the specified PV. 

We are considering making changes so that an IOC uploads its record list to
an LDAP server when its databases are loaded. Among other benefits this
would allow for wildcard queries using open source LDAP client libraries.
One of my papers at ICALEPCS 03 discusses some of the issues surrounding the
use of EPICS in WAN.

Jeff

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System