FAN should be turned off when connecting to ATP

[RichardExley]

ATP on shared infra does not support FAN. We need to have a mechanism to turn off FAN in our microservices when connecting to ATP-S. In the Python and NodeJS inventory microservices the time to instantiate the connection pool was dramatically reduced once FAN was disabled (15 seconds ro 1 second). Here is the current message from the order-helidon service:

Oct 06, 2021 11:35:35 PM oracle.simplefan.impl.FanManager configure
SEVERE: attempt to configure ONS in FanManager failed with oracle.ons.NoServersAvailable: Subscription time out

[RichardExley]

@paulparkinson Could this be why order-helidon takes so long to start up?

[paulparkinson]

indeed and this can be turned on and off via env prop

[RichardExley]

There appears to be a bug in latest UCP on this. Need to log bug.

[paulparkinson]

there is one. current workaround is apparently to use JDBC/UCP 21c with 19c ONS. will wait for official fix I think