I would like to increase the Admin Web UI session timeout in OpenVPN AS--i.e. the time you can leave a page in https://<server>/admin idle before it asks you to log in again. The docs at
https://docs.openvpn.net/command-line/managing-settings-for-the-web-services-from-the-command-line/ indicate that this timeout can be changed from its default of 30 minutes by setting sa.session_expire and that "This setting can be altered to any value in seconds."
Setting sa.session_expire lower does work. If I set it to 300, sessions time out after 300 seconds (five minutes) idle time. But the upper limit seems to be one hour. If I set it to 18000 or 36000 (five or ten hours), it times out after an hour.
This happens on OpenVPN AS 2.5.2 and 2.1.12, and on other versions at least as far back as 2.1.3 (the first version I used). I am using the Hyper-V OpenVPN AS Virtual Appliance (Ubuntu 16.04).
Is there any way this limit can be increased?