[Dsg-halla_gem] [EXTERNAL] Re: SBS GEM process variables

[Marc Mcmullen]

Hi Brad,

A week or so, I had them moved from the hall A eel s/n (192) to the hall A s/n (188) where the BB Rpi has been.

I’ll get with Brian to make sure the shell environment settings are correct.

Tomorrow, I’ll disable the wifi on that Rpi and see if that will fix the issue.

Regards,
Marc

________________________________
From: Brad Sawatzky <brads at jlab.org>
Sent: Monday, June 27, 2022 9:03 PM
To: Marc Mcmullen <mcmullen at jlab.org>
Cc: dsg-halla_gem at jlab.org <dsg-halla_gem at jlab.org>
Subject: [EXTERNAL] Re: SBS GEM process variables

Hi Marc,

That warning is due to the PV been mirrored on the channel access
gateway.  It is usually something of an inefficiency, but not fatal.
However, failure to pay attention to this kind of thing can cause PV
mirroring loops as a corner case.

In general you want something like the following in your shell environ:
  export EPICS_CA_ADDR_LIST="129.57.191.255 129.57.164.255 129.57.192.255 129.57.255.11"
The first three are gateway/broadcast addresses for Hall A networks.
The last is the "Hall A" channel access gateway that provides a bridge
to PVs outside the Hall A networks.
I believe it is considered best practice to also set:
  export EPICS_CA_AUTO_ADDR_LIST=NO


I did a 'caget' myself from within the Hall A network and got a bit of
an odd response:
  adaq at adaq2 2038% caget HAGEM:SBS:gas:ch41
  CA.Client.Diagnostic..............................................
    Message: "Ambiguous channel host (multiple IOC's have a channel by that name)"
    Severity: "Warning" Context: "Channel: HAGEM:SBS:gas:ch41 Accepted: adaqsc-xb.cha.jlab.org:5064 Rejected: adaqsc.jlab.org:5064 "
    Source File: ../service.c Line Number: 910
  ..................................................................
  HAGEM:SBS:gas:ch41            0.793

The response is from adaqsc-xb.cha.jlab.org.  That hostname resolves to
10.58.164.210, which is some internal subnet.  That seems a little odd
to me.  I'm not sure what is going on there, but Ole Hansen would be
able to tell you.  (I would have expected an RPi address on the 192 or
164.)

Have you updated the IP address for anything moved into the Hall (RPis,
etc) to get them off the 'dev' subnet and on to an appropriate Hall
network?

Note that you may also see weird results if you have both the wired and
wifi interfaces active.  The wifi interface on the RPi should be
permanently disabled.

-- Brad


On Mon, 27 Jun 2022, Marc Mcmullen wrote:

> Hi Brad,
>
> Since the SBS Rpi was moved to the hall I have noticed a warning about the
> pressure PVs during testing. Are there multiple servers running the HAGEM
> PVs?
>
> CA.Client.Exception...............................................
>
>     Warning: "Identical process variable names on multiple servers"
>
>     Context: "Channel: "HAGEM:SBS:gas:ch41", Connecting to:
> adaqsc.jlab.org:5064, Ignored: cagwops.acc.jlab.org:5064"
>
>     Source File: ../cac.cpp line 1320
>
>     Current Time: Mon Jun 27 2022 10:17:39.155967571
>
>
>
> Regards,
>
> Marc McMullen
>
> Sr. Instrumentation Designer
>
> Detector Support Group
>
> (757) 269-7738<tel:(757)%20269-7738>

--
Brad Sawatzky (he/him), PhD <brads at jlab.org> -<>- Jefferson Lab/SciComp/C111
Ph: 757-269-5947<tel:757-269-5947>  -<>-  Fax: 757-269-5235<tel:757-269-5235>  -<>- Pager: brads-page at jlab.org
The most exciting phrase to hear in science, the one that heralds new
  discoveries, is not "Eureka!" but "That's funny..."   -- Isaac Asimov
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/dsg-halla_gem/attachments/20220628/98b40dc4/attachment-0001.html>