Symptoms

  1. VE console does not work:

    Session Closed. Please click on Reset Console

  2. Apache's error_log (/var/log/httpd/error_log) contains the errors:

    [Wed Nov 22 21:11:27 2017] [error] [client 192.0.2.2] File does not exist: /var/www/parallels/html/websocket
[Wed Nov 22 21:12:37 2017] [error] [client 192.0.2.2] File does not exist: /var/www/parallels/html/websocket
[Wed Nov 22 21:12:48 2017] [error] [client 192.0.2.2] File does not exist: /var/www/parallels/html/websocket
[Wed Nov 22 21:20:59 2017] [error] [client 192.0.2.2] File does not exist: /var/www/parallels/html/websocket

Cause

Parameter ServerTokens set to 'OS' in global Apache configuration file:

[vz] ~:>grep ServerTokens /etc/httpd/conf/httpd.conf
ServerTokens OS

As a result of that configuration responses of web server contain the OS version which is not parsed by UI service.

Resolution

Parameter ServerTokens should be set to 'ProductOnly'.

Edit the configuration file of Apache /etc/httpd/conf/httpd.conf to 'ProductOnly':

[vz] ~:>grep ServerTokens /etc/httpd/conf/httpd.conf
ServerTokens ProductOnly

, and reload web server:

[vz] ~:>/etc/init.d/httpd reload
Reloading httpd:

Internal content