JTK – Notes and Ramblings Things we have found …

In the process of the upgrades discussed in the previous post – Ubuntu 18.04(Bionic Beaver) to 22.04(Jammy Jellyfish) there were additional issues for Webtrees and PHP.

The current release of webtrees (2.1) requires PHP 7.4, 8.0, 8.1 or 8.2. In the process of upgrading, PHP 8.1 was installed but lacked the required modules to function properly. This can be solved by a simple apt-get command to install the required pieces:

sudo apt-get install php8.1-{cli,common,curl,zip,gd,mysql,xml,mbstring,imagick,intl}

There is a discussion of this at https://www.webtrees.net/index.php/forum/help-for-2-0/35292-update-php-error-solved and https://www.webtrees.net/index.php/forum/help-for-2-0/35369-upgrade-ubuntu-to-20-04-02-broke-webtrees.

It is also worth noting the apache2 commands to enable/disable Apache PHP modules:

sudo a2dismod php7.4
sudo a2enmod php8.1

There is a discussion of installing multiple versions of PHP at https://tecadmin.net/how-to-install-php-on-ubuntu-22-04/ and https://linux.how2shout.com/how-to-install-php-7-4-on-ubuntu-22-04-lts-jammy-linux/. The articles discuss a PPA for the versions not in the standard apt sources. Once multiple versions are installed installed you can use

sudo update-alternatives --config php

to change versions. You can easily confirm the default version using “php -v”.

It was time to update the out of date server that is running the MythTV backend, so we went from 18.04(Bionic Beaver) to 20.04(Focal Fossa) to 22.04(Jammy Jellyfish). This is quite a jump. Most things survived the upgrades. According the Ubuntu we should have standard support until June 2027.

MySQL had an issue starting. The log at /var/log/mysql/error.log showed “unknown variable ‘query_cache_limit=1M'”. Turns out that query_cache_limit and query_cache_size are no longer valid in my.cnf for version 8.x. Removing these from the config file solved the problem. Read more at https://serverfault.com/questions/1042327/after-an-upgrade-to-ubuntu-20-04-lts-why-does-mysql-not-start.

There is the problem that after the upgrades the schema of the MythTV database was updated to 1376 instead of the 1348 on the clients. Off to do more upgrading…

It was also necessary to get a GUI view of the MythTV backend system. This machine hasn’t had a monitor connected in years, so the solution was VNC. The instructions at https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-vnc-on-ubuntu-20-04 got me started. The short version is “sudo apt-get install tightvncserver”, minor adjustment to ~/.vnc/xstartup and “vncserver” along with TightVNC from the PC with the correct IP:port from the command line got it working.

There’s a bit more in the tutorial if you want the VNC server running as a service or need to mess with resolution… For example, “vncserver -geometry 1280×800” to set the screen dimensions or “vncserver -kill :1” to close the server.