RE: CA issues on Linux

["Jeff Hill" <johill@lanl.gov>]

Some possible causes of trouble in this situation:

1)      There are multiple soft IOCs on this host _and_ EPICS_CA_AUTO_ADDR_LIST=NO _and_ the host IP for this host is in EPICS_CA_ADDR_LIST (this is a know limitation of typical ip kernels – see the CA ref manual). The only workaround currently is to configure clients to use broadcast when there are multiple soft iocs on one host, or alternatively to only run one soft ioc per host. I  have also implemented multicast support that fixes this issue, but the changes haven’t yet been merged it into a released version.

2)      There are some routing level issues – type “netstat –r”

3)      A local firewall is blocking the client’s search requests to port 5064, the soft IOC’s search responses to the client’s dynamically assigned port, or the client’s TCP connect requests.

4)      Something is amiss with CA’s auto configuration of its search address list (EPICS_CA_AUTO_ADDR_LIST=YES) on this version of linux. This can be investigated by calling the ca_client_status fuinction, passing a high interest level magnitude, from the test code.

5)      Issues with the exact spelling of the PV name

6)      A higher priority thread (than the ca server) in the soft IOC is using all of the cpu.

 

Jeff
______________________________________________________
Jeffrey O. Hill           Email        johill@lanl.gov
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Message content: TSPA

 

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From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-bounces@aps.anl.gov] On Behalf Of Cid, Florencio A
Sent: Thursday, September 01, 2011 11:18 AM
To: tech-talk@aps.anl.gov
Subject: CA issues on Linux

 

Hi all,

 

I have an  IOC running on a Linux PC (Redhat Enterprise 16.1).  But, I am having difficulty getting  a test CA client (running on the same Linux PC) to communicate with the IOC.  

 

Below are the errors being observed upon invoking the CA client. 

 

 

[control@control linux-x86_64]$ ./caExample controlHost:floRec1

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

    Warning: "User specified timeout on IO operation expired"

    Context: "ca_pend_io failure"

    Source File: ../caExample.c line 20

    Current Time: Thu Sep 01 2011 10:29:54.965120461

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

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

    Warning: "Virtual circuit disconnect"

    Context: "ca_get failure"

    Source File: ../caExample.c line 21

    Current Time: Thu Sep 01 2011 10:29:54.965502001

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

controlHost:floRec1 0.000000

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

    Warning: "User specified timeout on IO operation expired"

    Context: "ca_pend_io failure"

    Source File: ../caExample.c line 22

    Current Time: Thu Sep 01 2011 10:29:59.965721981

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

 

 

I tried searching the tech-talk archives, but couldn’t find anything related.   Any info/assistance will be greatly appreciated. 

 

 

Thanks in advance,

F. Cid