Re: Making two computers communicate.

[Ralph Lange <ralph.lange@gmx.de>]

This looks like a firewall issue on the Windows box.
Switch off the Windows firewall and retry.

~Ralph


On 02/09/2014 09:29, Vlad Andrei Rusu wrote:

So when trying to run those command on the Linux side, this is what it says:

[Vlad@Epics ~]$ /opt/Client/bin/linux-x86_64/caExample EpicsHost:ai1

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 Sep 02 2014 09:41:25.385035869

..................................................................

CA.Client.Exception...............................................

    Warning: "Virtual circuit disconnect"

    Context: "ca_get failure"

    Source File: ../caExample.c line 21

    Current Time: Tue Sep 02 2014 09:41:25.385503594

..................................................................

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 Sep 02 2014 09:41:30.385627321

..................................................................

EpicsHost:ai1 0.000000

[Vlad@Epics ~]$ caget EpicsHost:ai1

Channel connect timed out: 'EpicsHost:ai1' not found.

[Vlad@Epics ~]$ caput EpicsHost:ai1

No value specified. ('caput -h' for help.)

[Vlad@Epics ~]$ caput EpicsHost:ai1 2

Channel connect timed out: 'EpicsHost:ai1' not found.

[Vlad@Epics ~]$ 

The PCs can communicate, when I ping the Linux one (the one I am trying to get to read the values from Windows) from Windows, it appears a connection is established.

-----------------------------------------------------------------------------

Kind Regards

Rusu Vlad Andrei

T: (+004)0755.052.954

E: rusuvladandrei@gmail.com

A: Calea Ferentari 16 Bl.124A Ap.5 Sector 5, Bucharest, Romania

2014-09-02 10:26 GMT+03:00 Ralph Lange <ralph.lange@gmx.de>:

As Mark wrote: If both machines are on the same network, this should work without setting any EPICS environment variables.
Make sure that communication is not blocked by firewalls on your machines.
Note also that your otherwise identical example IOCs must use different names for the records - channel names within a Channel Access realm must be unique.

The easiest way to check Channel Access communication is using the command line tools (CA clients) that are part of base: caput, caget, camonitor, cainfo. They are available on Windows and Linux, so you can use any machine as client.

Good luck,
~Ralph

On 02/09/2014 07:49, Vlad Andrei Rusu wrote:

Sorry for the late response, I had some email issues last night and I was unable to respond.

Yes, one PC is running Windows x64 and one is running Scientific Linux x64, I have yet to decide which will be the host and which will be the client, I was thinking Linux should be the host and Windows the client but both of the hame the example IOC and example CA client installed.

I was thinking that connecting 2 PCs will be easier, just run the IOC as usual in a command line window ( bash or cmd ) and then make it so MEDM can read the data from the IOC that is running on the other PC through channel acces, and in my mind I just had to modify a variable for CA just to tell EPICS "send data here".

-----------------------------------------------------------------------------

Kind Regards

Rusu Vlad Andrei

T: (+004)0755.052.954

E: rusuvladandrei@gmail.com

A: Calea Ferentari 16 Bl.124A Ap.5 Sector 5, Bucharest, Romania

2014-09-01 16:50 GMT+03:00 Mark Rivers <rivers@cars.uchicago.edu>:

Hi,

You should not set any of the EPICS_CA_*ADDR* environment variables for that configuration.  The client and server are on the same subnet, so the default settings are fine.

> I am currently trying to run the IOC on a PC and get the data on another PC,

This is not clear. Is one PC running Windows and the other running Linux?  Which one is producing the data and which one would like to access the data?  Are both of the PCs running an IOC or is one PC running an IOC and the other running some other software that produces the data?  How does the computer that produces the data export that data?  As a socket server, etc.?

Give us some more details and we can provide advice.

Mark


________________________________
From: tech-talk-bounces@aps.anl.gov [tech-talk-bounces@aps.anl.gov] on behalf of Vlad Andrei Rusu [rusuvladandrei@gmail.com]
Sent: Monday, September 01, 2014 4:33 AM
To: tech-talk@aps.anl.gov
Subject: Making two computers communicate.

Hello

I am currently trying to run the IOC on a PC and get the data on another PC, both linked to the same switch. How should I run them? Windows should be the host and Linux the client? Also, to what should I modify the EPICS_CA_ADDR_LIST on the Host and on the Client? Should I make any more modifications?

Thank you in advance
-----------------------------------------------------------------------------
Kind Regards
Rusu Vlad Andrei
T: (+004)0755.052.954

E: rusuvladandrei@gmail.com<mailto:rusuvladandrei@gmail.com>

A: Calea Ferentari 16 Bl.124A Ap.5 Sector 5, Bucharest, Romania