LinuxHostingSupport

In case you remove a lot of data from the tables OR change the database structure, a de-fragmentation/optimizing of the database is necessary to avoid performance loss, especially while running queries. To avoid performance loss, optimize the database.

SSH to your server and execute:

mysqlcheck -o <databasename>

where, -o stands for optimize which is similar to defragmentation. You should look to defragment the tables regularly when using VARCHAR fields since these columns get fragmented too often.

Sometimes an error message “Unable to create PHostingManager object:Unable to set current ip address” appears in Plesk while managing a domain from Plesk -> Domains section. The complete error is as follows:

"Unable to create PHostingManager object:
Unable to set current ip address:
IP address is missing"

This problem appears when an IP assigned to a domain is not assigned to the ‘Owner’ of the domain. To fix the issue, login to Plesk and assign the IP to the owner:

Plesk --> 'Settings' --> "IP Addresses" -->  click the number 
 under the 'Users' coloumn in front of the IP address -->
 Assign the IP to the owner.

This will update the ‘psa’ database and allow the user to manage the domain from Plesk.

On a VPS, there are 2 ways to mount OR secure /tmp and /var/tmp partitions with the noexec,nosuid option. One way is to mount these partitions from the Host Node (hosting provider can do this) and the other way is to mount them from within the VPS.

1) Login to the Node server and execute the following command:

# vzctl set VEID --bindmount_add /tmp,noexec,nosuid,nodev --save 
# vzctl set VEID --bindmount_add /var/tmp,noexec,nosuid,nodev --save

The “bindmount_add” option is use to mount the partition inside the VPS. The ‘VEID’ is the VPS ID you are working on.

2) The second option is to mount these partition from within the VPS itself. It is useful incase you don’t have access to the Node server. To mount /tmp and /var/tmp from within the VPS, execute:

# mount -t tmpfs -o noexec,nosuid,nodev tmpfs /tmp 
# mount -t tmpfs -o noexec,nosuid,nodev tmpfs /var/tmp

To check the mounted ‘tmp’ partitions, execute

# mount | grep tmp 
 tmpfs on /tmp type tmpfs (rw,noexec,nosuid) 
 tmpfs on /var/tmp type tmpfs (rw,noexec,nosuid,nodev) 

Related Links:

 How to Secure /tmp on Dedicated server?

An update/upgrade on the existing Drupal website may result in a following error message on the website:

"PHP Fatal error:  Call to undefined function user_access() 
 in /home/user/modules/ad/ad.module on line xxx"

The solution is to update a “status” entry in the Drupal Database. Access your Drupal database either from the Mysql prompt OR using a 3rd party application like phpMyAdmin.

1) Open the table called “System”.

2) Search for the entry “modules/user/user.module” in the “filename” column.

3) Change the value of ‘status’ variable from 0 to 1.

4) Save.

This is it.

Note: If the value of ‘status’ variable is already 1, change it to ‘0’ and then reset back to ‘1’. It should fix the issue.

What is Frame Forwarding and How it is set?

A few lines of Explanation:

Frame forwarding (redirection) of a domain is different than normal forwarding of a domain.

In Frame Forwarding, the visitors are redirected to another site, but the destination address is not displayed in the address bar, so they are not aware of the redirection as opposed to “Normal Forwading” (also called Parked domain).

In Normal Forwading the web site visitors are redirected to another site and the destination address is displayed in the address bar, so the visitor is aware about the redirection.

For example, suppose the main website is abc.com and we frame forwarded xyz.com to it. When we access xyz.com, the URL in the address bar of the browser will stay as it is and the contents will be fetched from abc.com. The user won’t notice the redirection.

Solution:

Using the above domain names as example, in order to set Frame Forwarding for xyz.com, first add the domain on the server as we normally do and add the following code in the index.html file

<frameset rows="100%", *' frameborder=no framespacing=0 border=0> 
<frame src="http://www.abc.com/"></frame> 
</frameset>

This is it.

A Drawback of the above method and a Solution for it:

As you will be setting up a redirection in the index.html file, any other file/directory accessed using a direct URL ( i.e. for example: xyz.com/anyfilename) will result in a “404 Not Found” error.This is because the request will bypass the redirection set in the index.html file and will search for the file under the xyz.com itself.

To overcome this problem, add xyz.com as a “ServerAlias” in the VirtualHost entry of abc.com. Edit the Apache configuration

vi /etc/httpd/conf/httpd.conf

Search for the VirtualHost entry of abc.com and make sure the “ServerAlias” line look like the following

ServerAlias www.abc.com xyz.com www.xyz.com

Save the file and restart the Web server

service httpd restart

Now, directly accessing a file or directory of a target domain using the alias domain name will also work.