Issue dist-upgrade Ubuntu 18.04 to Ubuntu 20.04 mySQL FAIL

[iWiLL]

Server operating system version

Ubuntu 18.04

Plesk version and microupdate number

18.0.62

I did the dist-upgrade process from Ubuntu 18.04 with mySQL to Ubuntu 20.04 and didn't get the message "dist-upgrade process from Ubuntu 18.04 to Ubuntu 20.04 is supported with MariaDB scenario only." Now I am stuck at 24. Execute the dist-upgrade command because mySQL is not starting anymore

● mysql.service - MySQL Community Server
     Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
     Active: failed (Result: exit-code) since Wed 2024-06-26 23:23:13 CEST; 12s ago
    Process: 153947 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=1/FAILURE)

Jun 26 23:23:13 srv1.torund.de systemd[1]: mysql.service: Scheduled restart job, restart counter is at 5.
Jun 26 23:23:13 srv1.torund.de systemd[1]: Stopped MySQL Community Server.
Jun 26 23:23:13 srv1.torund.de systemd[1]: mysql.service: Start request repeated too quickly.
Jun 26 23:23:13 srv1.torund.de systemd[1]: mysql.service: Failed with result 'exit-code'.
Jun 26 23:23:13 srv1.torund.de systemd[1]: Failed to start MySQL Community Server.

Is there a way to rollback or solve this issue?

 

[iWiLL]

More error messages:

Setting up mysql-server-8.0 (8.0.37-0ubuntu0.20.04.3) ...
update-alternatives: warning: forcing reinstallation of alternative /etc/mysql/mysql.cnf because link group my.cnf is broken
update-alternatives: warning: not replacing /etc/mysql/my.cnf with a link
Renaming removed key_buffer and myisam-recover options (if present)
ERROR: Unable to start MySQL server:
2024-06-26T22:13:51.803234Z 0 [ERROR] [MY-000077] [Server] /usr/sbin/mysqld: Error while setting value 'ONLY_FULL_GROUP_BY,NO_ZERO_IN_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION' to 'sql_mode'.
2024-06-26T22:13:51.805803Z 0 [ERROR] [MY-010119] [Server] Aborting
Please take a look at https://wiki.debian.org/Teams/MySQL/FAQ for tips on fixing common upgrade issues.
Once the problem is resolved, run apt-get --fix-broken install to retry.

 

[Mikhail_S]

Hello @iWiLL

In general, I would recommend restoring the server from a backup/snapshot. Then, you will be able to replace MySQL with MariaDB and start dist-upgrade from scratch.
Replacing MySQL with MariaDB in Plesk

---

As for the existing issue, it seems MySQL could get non-configured. There is a chance this behavior might be fixed by using this command:

systemctl enable mysql

Then, MySQL must be replaced with MariaDB.
However, I can not guarantee dist-upgrade will continue correctly after that. Other issues could have arisen alongside MySQL's one.