Key is stored in legacy trusted.gpg keyring

As described in the post [here]( you would need to export the key to its own file under the trusted.gpg.d directory.

So for example if the warning is for something like forticlient, first find the key using sudo apt-key gpg list and then taking the last eight characters and removing the space, export the key to its file (ie forticlient.gpg)

sudo apt-key export 5E54716D | sudo gpg --dearmour -o /etc/apt/trusted.gpg.d/forticlient.gpg 

PostgreSQL upgrading from 9.6 to 15.3 has authentication failed (PG::ConnectionBad)

After upgrading a PostgreSQL instance from version 9.6 to the currently latest version 15.3, your application cannot connect to the server, giving an authentication error even if the user/password used is still the same.

This seems to be the result of a change in the method used in the pg_hba.conf file.

Version 9.6 uses md5 but version 15.3 uses scram-sha-256

Changing this in the file pg_hba.conf file from scram-sha-256 to md5 and reloading the configuration file from inside the database with select pg_reload_conf(); , results in the application being able to connect to the database server again.

Update: It is possible to use the recommended scram-sha-256 hash, by doing the following:

  • Uncomment the line with #password_encryption = scram-sha-256 # scram-sha-256 or md5 in file /var/lib/postgresql/data/pgdata/postgresql.conf
  • reload the configuration in the database select pg_reload_conf();
  • recreate the password with the new encryption production=# alter user user_name with password 'password';

failed to create fsnotify watcher: too many open files

This is quite possibly caused by one of the limits set too low. It is common when using promtail (with Loki for example) to tail log files.

One of the ways to get over this is to increase the value (in this example max_user_instances) either for the session or by making the change permanent by adding to a file (/etc/sysctl.conf).

For testing and doing it for the session, login to the affected server and do the following

ubuntu@server:~$ cat /proc/sys/fs/inotify/max_user_instances 
ubuntu@server:~$ sudo sysctl fs.inotify.max_user_instances=8192
fs.inotify.max_user_instances = 8192
ubuntu@server:~$ cat /proc/sys/fs/inotify/max_user_instances