Experimental Physics and
Industrial Control System

"Vodopivec, Klemen via Tech-talk" <tech-talk at aps.anl.gov> · Fri, 9 Apr 2021 15:44:40 +0000

Hi,

I apologize if this has been answered before, but a simple search came up empty.

We’re trying to use PVA on our segmented network for some structured tabular data. On the given network segments, CA works fine for years without the need for CA gateway but with some small help from the router mangling the broadcast (discovery) requests. What appears to be working for CA on port 5064, it doesn’t for PVA on port 5076 even after adding similar rule to the router.

The use case is as follows:

caget/pvget client is on a 192.168.75.100/22 with bcast address 192.168.75.255. softIocPVA server is on a 192.168.83.100/22 with bcast address 192.168.83.255. caget requests work, but pvget don’t. We have traced it to be that the router turns UDP discover message destined to 192.168.83.255 into 255.255.255.255 when pushing it to the 192.168.80.0 segment. The CA server is listening on 0.0.0.0:5064 and it catches that, but the PVA server is listening on 192.168.83.255:5076 and it doesn’t see messages for 255.255.255.255. 

We’re working with networking guys to understand why router turns 192.168.83.255 into 255.255.255.255, but I was wondering if anyone else has tried similar setup and whether there’s any workaround. These tests were done with EPICS 7.0.4.1

Thanks, Klemen

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System