Re: procServ, not CA Re: [Fwd: RE: Soft IOCs and Port Numbers]

[Ralph Lange <Ralph.Lange@bessy.de>]

 On 24.09.2010 10:21, Kasemir, Kay wrote:
> Hi:
>
> Actually, regarding multiple soft IOCs on the same host at the SNS,
> I don't think we have any severe Channel Access issues.
> We no longer set the EPICS CA SERVER PORT to a unique number.

You might not think so, but you do:

Any client that does not use UDP broadcasts for name resolution will 
only see an arbitrary one of the soft IOCs on that server.

Try it: Using EPICS_CA_AUTO_ADDR_LIST=NO (to suppress broadcasts) and 
EPICS_CA_AUTO_ADDR_LIST=<your server> (to allow directed UDP traffic to 
your soft IOC server), try any CA client (e.g. caget) to read a variable 
on one of your soft IOCs. Depending on the number of soft IOCs on your 
server, you will find a behaviour between connecting every time (only 
one soft IOC) and almost never (many soft IOCs).

There is a warning message at IOC boot to inform you of that possibly 
unexpected behaviour.

As long as all your clients use broadcasts, you're fine.

Sorry...
Ralph