Experimental Physics and
Industrial Control System

Mark Rivers <[email protected]> · Tue, 19 Aug 2014 14:09:53 +0000

Hi Bertrand,

What is the network configuration of the IOC machine and the medm machine?  Are they running on the 

1) Same computer
2) Different computer on same subnet
3) Different computers on different subnets?

If 1) or 2) then you should not set the EPICS_CA_ADDR_LIST environment variables at all, the defaults should work.

If 2) then you may need to disable iptables on both machines.

> Stopping iptables did manage to solve some port issues (when starting the ioc the shell gave a warning about the default 
> port being unsuitable and giving a random port) but the problem with the ./caExample persists and MEDM is still not getting any values.

The warning you saw is normal if you have 2 IOCs running on the same machine.  Disabling iptables should have no effect on that warning. I suspect the warning went away for a different reason, i.e. that you were no longer running 2 or more IOCs.

Mark

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Martin L. Smith
Sent: Tuesday, August 19, 2014 8:27 AM
To: [email protected]
Subject: Re: New users - Channel Access Clients issues

Hi Bertrand,

I assume you are using the EPICS_CA_ADDR_LIST and EPICS_CA_AUTO_ADDR_LIST
because your CA client is not running on the same network as the IOC.

I think that if you do not have a firewall between your networks but there
is in fact a network route through a router then the above environment
variables should take care of the CA client side connections but the IOC
must know how to send information back to the client.

For that you will likely need to have similar environment variables set in
the IOC st.cmd file. Otherwise you could run a PV gateway between the networks.

Also if you have EPICS_CA_AUTO_ADDR_LIST=YES then you likely do not need to
have the broadcast address 192.168.163.255 in your EPICS_CA_ADDR_LIST; however,
you might need to specifically include the IP address of the router for both
the CA client as well as the IOC.

Marty

On 08/19/2014 08:07 AM, Bertrand de Boisdeffre wrote:
> Dear EPICS users,
>
> We installed Epics base 3.14.12.3 on a computer using Scientific Linux.
>
> Then we managed to create, build and run the IOC example application included
> with the EPICS base.
>
> Now, we would like to create one CAClient to access the PV.
>
> Then we configured the /etc/profile file and added the necessary lines:
>
> EPICS_HOST_ARCH="linux-x86_64"
>
> export EPICS_HOST_ARCH
>
> EPICS_BASE=/opt/epics/base-3.14.12.3
>
> export EPICS_BASE
>
> PATH=$PATH:/opt/epics/base-3.14.12.3/bin/linux-x86_64
>
> EPICS_CA_AUTO_ADDR_LIST=YES (tried this too, but it did not work)
>
> export EPICS_CA_AUTO_ADDR_LIST
>
> EPICS_CA_ADDR_LIST="192.168.163.97 192.168.163.255"
>
> export EPICS_CA_ADDR_LIST
>
> and we am unable to reach any PV in the example app included in Epics.
>
> We am running the example app by running st.cmd in terminal, we can see the PVs
> inside Iocshell but when I try to connect the PV to a graphical text monitor in
> MEDM, the Graphical Object is not connected to the PV inside the IOC.
>
> PV Info inside MEDM says:
>
> TYPE: TYPENOTCONN
>
> HOST: <disconnected>
>
> The PV name is correct, we think: rootHost:ai1.VAL and tried
> rootHost:aiExample1.VAL and they are not receiving any values from the IOC.
>
> When we try to run caExample we get the following errors:
>
> [root@Epics O.linux-x86_64]# ./caExample rootHost:ai1.VAL
>
> CA.Client.Exception...............................................
>
>      Warning: "User specified timeout on IO operation expired"
>
>      Context: "ca_pend_io failure"
>
>      Source File: ../caExample.c line 20
>
>      Current Time: Tue Aug 19 2014 14:54:46.378283619
>
> ..................................................................
>
> CA.Client.Exception...............................................
>
>      Warning: "Virtual circuit disconnect"
>
>      Context: "ca_get failure"
>
>      Source File: ../caExample.c line 21
>
>      Current Time: Tue Aug 19 2014 14:54:46.378688325
>
> ..................................................................
>
> CA.Client.Exception...............................................
>
>      Warning: "User specified timeout on IO operation expired"
>
>      Context: "ca_pend_io failure"
>
>      Source File: ../caExample.c line 22
>
>      Current Time: Tue Aug 19 2014 14:54:51.378812388
>
> ..................................................................
>
> rootHost:ai1.VAL 0.000000
>
> We thank you in advance for your support.
>
> Best regards,
>
> ------------------------------
>
> Bertrand DE BOISDEFFRE & Vlad RUSU
>
> ELI-NP, Horia Hulubei National Institute for Physics and Nuclear Engineering
>
> 30 Reactorului Street,
>
> 077125 Magurele, Romania
>
> +4021 404 50 89 / 021 404 50 89
>
> www.eli-np.ro <http://www.eli-np.ro/>
>

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System