SolusVM getting a blank page after the update to 1.20.09 or higher on CentOS 5 node.

Symptoms 

SolusVM getting a blank page after the 1.20.09 update on CentOS 5 node

The version of PHP is 5.1:

# php -v

lighttpd web server serves the requests to Master SolusVM web interface

The following error in error log:

# tail -fn0 /var/log/lighttpd/error.log
2018-12-05 16:41:49: (mod_fastcgi.c.2538) FastCGI-stderr: PHP Fatal error: Call to undefined function json_decode() in /usr/local/solusvm/includes/config.php on line 102

Cause

System PHP does not have json module enabled

Resolution

1. Connect to the Master SolusVM server via SSH
2. Update the PHP to the packages by symlink PHP to svmstack PHP using the below command.
   

   # mv /usr/bin/php /usr/bin/backup-php
   # ln -s /usr/local/svmstack/php/bin/php /usr/bin/php

3. Switch from lighttpd to svmstack-nginx service:
   • install repository

     # yum install solusvm-release

   • shutdown lighttpd service

     # service lighttpd stop

     # chkconfig lighttpd off

   • install nginx and legacy configuration file for master
     

     # yum install svmstack-nginx svmstack-nginx-legacy-master-config

   • install nginx and legacy configuration file for slave
     

     # yum install svmstack-nginx svmstack-nginx-legacy-slave-config

   • start new service

     # service svmstack-nginx restart

     # service svmstack-fpm restart

   For more details check the following article

For the issues with the slave node the following article can be useful
Master SolusVM fails to connect to the slave node: Connection Failed Debug Data: ERROR:4