Julian Feinauer created PLC4X-132:
-------------------------------------
Summary: [S7] Communication to S7 PLC dies in some situations
Key: PLC4X-132
URL: https://issues.apache.org/jira/browse/PLC4X-132
Project: Apache PLC4X
Issue Type: Bug
Components: Driver-S7
Affects Versions: 0.4.0
Reporter: Julian Feinauer
The following is from the Mailing Thread [1]:
In the last weeks we observed multiple times strange behavior when connecting
to Siemens S7 devices.
We have not yet been able to trace it down entirely but I have the assumption
that it is an issue with the PooledPlcDriverManager.
Whats the issue?
When doing requests (either via OPM or the “regular” API) we come at a point
where all subsequent requests simply fail (and in some cases we were no longer
able to send requests to the PLC from other instances, so it looks like the
internal server went down).
Whats the setup?
When I remember correctly, all situations where this occurred used the Pool as
Basis.
We had it both with OPM and the normal API but NOT with the Scraper.
I remember that I spent like a hole day at the Hackathon in Mallorca to get all
timeout things to work correctly, as the S7 does not like when you simply
cancel your request futures.
Currently there are two “suspects” from my side.
First, the pool calls the “.connect()” method on a now Connection it
establishes but by API convention you also have to do that in your code so it
gets called multiple times, which could fuck up stuff.
Second, connection can also time out (but its no future in our API) so in the
Scraper I implemented it as Future with timeout (as I’m unsure how everything
behaes if the pool starts to initialize a connection but then the “waitTime”
times out and it abandons this).
[1]
https://lists.apache.org/thread.html/328a6780b34b4fd2e3298e9e70340293ebb397b1978a7b631030067e@%3Cdev.plc4x.apache.org%3E
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
