Migration from Confixx to Plesk fails: Command execution failed on the source server 'confixx' () with non-zero exit code

Symptoms

1. Error in Tools & Settings > Migration & Transfer Manager > List of Subscriptions > example.com > Details:

   PLESK_INFO: stderr: mysqldump: Got error: 2002: Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2) when trying to connect

2. Migration from Confixx server fails:

   CONFIG_TEXT: Failed to perform action: Fetch data from source Confixx Cause:
   Error creating migration dump: Command execution failed on the source server 'confixx' (203.0.113.2) with non-zero exit code. command: cd /root/plesk_migrator/plesk_migrator-mfjoyglk894cagi7xh9g3ra87eqdxovf/pmm_agent; /usr/bin/perl Confixx.pl --dump-all --configuration-only --server -v 5 > dump.log 2>&1 exit code: 2 stdout: stderr: That is a critical error, migration was stopped.

Cause

MySQL service is stopped on the source server. 

Resolution

1. Login to the source server over SSH
2. Start MySQL service:

   # service mysqld start || service mysql start || service mariadb start

Additional information

If MySQL cannot start, find log location at /etc/my.cnf, check the log for errors and search in Knowledge Base for solution.