Unable to OTAA my devices

[Nab]

I am using Arduino Nano with the Sx1276 Lora chip and Rak7244 Gateway. ChirpStack Gateway-bridge, Network Server and App server are installed on a Ubuntu server.
How can I check Packet Forwarder logs?
Thanks

[Nicholas]

Log on to the gateway by command:

tail -f/var/log/syslog

View Packet Forwarder log