To upgrade Wialon Local from version 2104 to version 2204, follow the steps below.

1. Before upgrading Debian, you should retain the old versions of the python and libpython packages. For this purpose, run the following command:

   apt-mark hold python python2.7 libpython2.7

2. Upgrade the operating system Debian to the version 11 (Bullseye).

3. Upgrade Node.js  to the version 12.x, by running on behalf of the main user (root) the following commands:

   cd /home/wialon/wlocal/
   service wlocal stop
   ./adf_script stop
   apt-get install -y curl
   curl -sL https://deb.nodesource.com/setup_12.x | bash -
   apt-get install -y nodejs npm
   npm -g install forever
   npm install
   chown -R wialon:wialon /home/wialon/
   service wlocal restart

4. Install the version 2204 of Wialon Local.

Check the availability of your sites after they restart. 

Node.js upgrade instructions are also available on the official site of the Node.js developer.