When upgrading Wialon Local from version 1804 to version 1904, follow the steps below.

1. Make sure that the Debian operating system has been upgraded to version 9 (Stretch).
   • When updating from Debian 8 to Debian 9, add a line “include /etc/nginx/modules-enabled/*.conf” to the file  /etc/nginx/nginx.conf . Here is an example of the received file:

   user www-data;
   worker_processes  2;
   worker_rlimit_nofile 65535;
   include /etc/nginx/modules-enabled/*.conf;
   
   error_log  /var/log/nginx/error.log;
   pid        /var/run/nginx.pid;
   
   events {
          worker_connections  65535;
   }
   
   http {
          include       /etc/nginx/common/*;
          include       /etc/nginx/conf.d/*;
   }

2. Add additional options (listed below) to the nginx configuration files for the admin site (/etc/nginx/conf.d/lcm.conf). Add the options to the location element of the server section of the lcm.conf file and to the configuration of other nginx involved in proxying requests. This is required to activate work using web sockets.

   proxy_set_header Upgrade $http_upgrade;
   proxy_set_header Connection "Upgrade";
   

   Example of the lcm.conf configuration file:

   server {
       listen        80;
       server_name    10.10.10.10;
       client_max_body_size 10000m;
       proxy_read_timeout 500;
       location /50x.html {
           root /home/wialon/wlocal/nginx/www/nginx-default;
       }    
       location / {
           if ( $args ~* dns-test ) {
               echo 1;
           }
           proxy_set_header Upgrade $http_upgrade;
           proxy_set_header Connection "Upgrade";       
           proxy_pass         http://localhost:8080;
       }
       access_log /var/log/nginx/lcm.access.log;
   }
   
   

3. Install the ripgrep utility. It is required for quick reading of statistical information about the status of the server.

   wget --no-check-certificate http://ftp.br.debian.org/debian/pool/main/r/rust-ripgrep/ripgrep_0.10.0-2_amd64.deb -O /tmp/ripgrep.deb
   dpkg -i /tmp/ripgrep.deb
   

4. Install the version 1904 of Wialon Local.