Closing dangling sessions

[d6stringer]

I am very new to this so forgive my ignorance.
I'm working with a Siemens S7-1200 OPC server and I'm trying to gather some info from it. That part is going relatively smoothly. I have another question about my subscription that I will post separately/later if I don't solve it on my own.

The issue I'm having is that if I kill my client the session stays active on the server, so with a maximum session count of 5 I'm running into where my server rejects a new connection. I'm trying to come up with a way to check for and close out those dangling sessions.

I've figured out a way to check the CurrentSessionCount:

session_node = client.get_node("i=2277") # i=2277 is the CurretSessionCount
session_count = session_node.get_value()
print("Session count is: ", session_count)

Which is great, tells me how close I am to my limit. But that's about as much as I can do at this point. What I'd like to do is check for sessions and close any old/unused ones.

Alternatively, is there a way to rejoin a session already established? I have tried "activate_session" but that seems like it's just opening up a new one again.

Another consideration is getting old sessions to time out but I'm not sure that can be done.

thanks in advance.

[AndreasHeine]

the session is stored serverside the only way to get around is to shorten sessiontimeout in the s7

[AndreasHeine]

while connect server and client negotiate the timeout!

[d6stringer]

I found these in the Client class and altered them:

self.secure_channel_timeout = 360000  # was 1 hour, changed to 5 minutes
self.session_timeout = 360000  # was 1 hour changed to 5 minutes

that seems to have done the trick. only question is did I do something bad?

[AndreasHeine]

no its just a warning that the server did not accept the requested client timeouts and send the client the once to use ;)

[AndreasHeine]

self.session_timeout != response.RevisedSessionTimeout

python-opcua/opcua/client/client.py

Line 404 in 3012acf

_logger.warning("Requested session timeout to be %dms, got %dms instead",

[d6stringer]

A little derp on that last comment. you can easily edit

client.session_timeout 

inline and it accomplishes the same thing as changing the class (duh).

[AndreasHeine]

reuse of session is not implemented!