Monitoring - Add Certificate to Zabbix

By default, zabbix runs on http and sends all login data in cleartext which is not ideal in terms of security. This is a short writeup on how to configure the zabbix-frontend to run on https.

First up, you'll need a certificate. This can be obtained from your internal CA or you can generate a self-signed certificate using this handy command:

 [archy@zabbix ~]$ sudo openssl req -x509 -nodes -days 3650 -newkey rsa:4096 -keyout /etc/pki/tls/private/zabbix.archyslife.lan.key -out /etc/pki/tls/certs/zabbix.archyslife.lan.cert

Now that you've got the certificate, reconfigure httpd to also listen on port 443. Add this line to /etc/httpd/conf/httpd.conf:

 [archy@zabbix ~]$ sudo vim /etc/httpd/conf/httpd.conf

 Listen 443

Now, let's configure the zabbix virtualhost. The virtualhost config is a slightly altered version of the default version provided by zabbix.

 [archy@zabbix ~]$ sudo vim /etc/httpd/conf.d/zabbix.conf

 Alias /zabbix /usr/share/zabbix
 <VirtualHost *:443>    
  SSLEngine on  
  SSLCipherSuite AES256+EECDH:AES256+EDH  
  SSLProtocol ALL -SSLv2 -SSLv3  
  SSLHonorCipherOrder on  
  SSLCertificateFile /etc/pki/tls/certs/zabbix.archyslife.lan.cert  
  SSLCertificateKeyFile /etc/pki/tls/private/zabbix.archyslife.lan.key  
  <Directory "/usr/share/zabbix">  
   Options FollowSymLinks  
   AllowOverride None  
   <IfModule mod_authz_core.c>  
    # Apache 2.4  
    Require all granted  
   </IfModule>  
   <IfModule !mod_authz_core.c>  
    # Apache 2.2  
    Order allow,deny  
    Allow from all  
   </IfModule>  
   <IfModule mod_php5.c>  
    php_value max_execution_time 300  
    php_value memory_limit 128M  
    php_value post_max_size 16M  
    php_value upload_max_filesize 2M  
    php_value max_input_time 300  
    # Removed in PHP 7  
    php_value always_populate_raw_post_data -1  
    php_flag session.auto_start off  
    php_value mbstring.func_overload 0  
    php_value date.timezone Europe/Prague  
   </IfModule>  
  </Directory>  
  <Directory ~ "^/usr/share/zabbix/(conf|app|include|local)/">  
   <IfModule mod_authz_core.c>  
    # Apache 2.4  
    Require all denied  
   </IfModule>  
   <IfModule !mod_authz_core.c>  
    # Apache 2.2  
    Order deny,allow  
    Deny from all  
   </IfModule>  
   <files *.php>  
    <IfModule mod_authz_core.c>  
     # Apache 2.4  
     Require all denied  
    </IfModule>  
    <IfModule !mod_authz_core.c>  
     Order deny,allow  
     Deny from all  
    </IfModule>  
   </files>  
  </Directory>  
 </VirtualHost>

The highlighted lines are responsible for SSL. Now that it's configured, check the syntax using httpd:

 [archy@zabbix ~]$ sudo httpd -t

If that returns 'Syntax OK', you can go ahead and restart the httpd.service:

 [archy@zabbix ~]$ sudo systemctl restart httpd.service

That's it, zabbix should not be reachable through https only.

Keep in mind that using a self-signed cert is not the way to go and the cert should be replaced with a cert issued by a trusted CA, such as one hosted by FreeIPA or Active Directory.

Feel free to comment and / or suggest a topic.

Comments

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