Experimental Physics and
Industrial Control System

Michael Davidsaver via Core-talk <[email protected]> · Sun, 12 Jan 2020 09:50:49 -0800

On 1/12/20 9:19 AM, Mark Rivers wrote:
>> When combined with a lack of coordination within the implementations, each process with both a PVA client and server will always bind twice to 5076.
> Is that is what is causing the "Error binding" message?  What PVA client would they be running.  They are running the PVA server in base 7, including qsrv.

This is, and always has been, happening on all targets.
It should not be causing a problem if all sockets bound to 5076
set the SO_REUSEADDR (or sometimes SO_REUSEPORT) socket option.
This is 'epicsSocketEnableAddressUseForDatagramFanout()' in Base.
vxWorks currently uses the posix version.

https://github.com/epics-base/epics-base/blob/468f965dc2753e7a381dcc09dd9b5656e3149ac2/modules/libcom/src/osi/os/posix/osdSockAddrReuse.cpp#L42

While I would expect this would have been noticed before now,
one possibility is that SO_REUSEADDR doesn't have the desired effect
on vxWorks.  At least not for UDP sockets.

There is no test coverage, and CA has never needed it to work on this OS.

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System