Add Multiple shared IPs in WHM

First, you need to create a /var/cpanel/mainips/ directory, if it doesn’t exist:

mkdir /var/cpanel/mainips/

Then, create a /var/cpanel/mainips/root file, with the following content:

1.2.3.4
3.4.5.6

Basically, each line is an additional shared IP in WHM. That’s it!

Change main shared IP of cpanel server

You can setup your main shared IP from

WHM >> Main >> Server Configuration >> Basic cPanel/WHM Setup >> Main Shared Virtual Host IP

and you can see your ip address usage from :

WHM >> Main >> IP Functions >> Show or Delete Current IP Addresses

Invalid kernel, or some kernel modules are not loaded

#vzlist -a | grep IP
ID         -stopped   IP   servername

#vzctl start ID

Invalid kernel, or some kernel modules are not loaded
Container start failed (try to check kernel messages, e.g. “dmesg | tail”)

 The first thing you need to check is if vz service is functional OR not. To start, use command as below.

 /etc/init.d/vz start
All the containers/VPS will start one by one.
It might be that vz service is not set to On when server boots. You can check it with command as below.
chkconfig –list | grep vz
If it’s set to Off, you need to switch it On with command below.
chkconfig on vz

Hide the Apache Version via httpd.conf

Open your httpd.conf file using text editor such as vi:
   
vi httpd.conf

 Append/modify config directive as follows:

ServerTokens ProductOnly
ServerSignature Off

 Save and close the file. Restart Apache web server:

 # /etc/init.d/httpd restart

Hiding Apache server versions and OS details via Webmin

These simple steps will help you if you use Webmin

1. Log into Webmin
2. From the navigation onthe left click on "Servers"

3. Click on "Apache Webserver" from expanded list
4. Click on "Global configuration" tab
5. Click on the "Miscellaneous" icon
6. From "Server HTTP header" option, select: Product only.

7. Click "Save"
8. Then from the top right corner of the next screen click "Apply Changes" to make the changes live.

How to Enable and Disable Website Maintenance Mode in plesk

If Maintenance mode is swich on, your site may offline. You may get error similar to code error like 'Calling LoadLibraryEx on ISAPI filter'  when view site through a browser.

You can view this error "Maintenance mode is swich on, your site may offline"  near the domain name under 'Websites and domain'  section on plesk contrl panel.

To switch on the maintenance mode for a website to suspend a site temporarly:

1. Go to the Websites & Domains tab.
2. Click Website Maintenance Mode (in the Advanced Operations group).
3. If you have several websites, locate the site you want to temporarily suspend, and click the corresponding Manage link.
4. Select the Switch on the maintenance mode for website checkbox.
5. Click OK.

If the custom error documents option is switched on for the site, then you can edit the "503 Service Temporarily Unavailable" document to include your own text

To switch off the maintenance mode and put a site back online:

1. Go to the Websites & Domains tab.
2. In the list of your websites, locate the website you want to put back online. It should be accompanied by the Switched off for maintenance status indicator.
3. Click the corresponding Change link.
4. Clear the Switch on the maintenance mode for website checkbox.
5. Click OK.