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Repair operations performed through phpMyAdmin or the control panel on large MySQL database files may not complete or may cause issues. Therefore, it is more reliable to repair large MySQL databases via SSH on Linux servers.

Connect via SSH and make sure you are the superuser (root). Enter the following command in the command line:

mysqlcheck -r [database name]

mysqlcheck is the command used to check databases. The -r parameter performs a Repair operation.

If the above command does not work, you can perform the operation directly by specifying the MySQL files directory from the Linux command line:

myisamchk -r /var/lib/mysql/[database name]/*

Note: Before performing a MySQL repair, make sure the server has sufficient disk space.

The SSL protocol is the encryption standard between users and e-commerce sites. An SSL connection is a mechanism created to prevent tampering or corruption of transmitted information. SSL provides a secure connection for companies and customers when sending private information to websites. It protects personal information such as credit card numbers and prevents them from being intercepted by third parties.

It is quite simple to tell if a website has an SSL certificate. If there is a green lock icon in the browser’s address bar and the site is accessed via the https:// protocol, the site has an SSL certificate. Your connection is encrypted and your information is secure.

You can also check whether a site has an SSL certificate at this address.

EV (Extended Validation) SSL

EV SSL is a certificate designed as the highest level of security measure. EV SSL, which stands for Extended Validation, appears as a green bar in the address bar. Unlike other certificates, EV SSL provides corporate identity and special trust as a company. The open institutional information of the company owning the website appears on the green address bar, providing a definitive measure against identity theft. This certificate is supported by browsers such as Internet Explorer, Chrome, Firefox, Opera, and Safari.

Requirements for SSL Certificate Installation

For SSL certificate installation on your site, your site must be running on a dedicated IP address. SSL certificates cannot be installed on sites running on a shared IP address. Even if installed, the SSL certificate will give an error. After the IP change, certificate installation procedures are completed. Once the certificate installation is complete, you need to update the http references in your software to https.

For CentOS & cPanel servers, here are the steps to take for the SSLv3 vulnerability that recently emerged:

nano /usr/local/apache/conf/includes/pre_main_global.conf

Open the file and add the following code:

(For CentOS 6)

SSLHonorCipherOrder On

SSLProtocol -All +TLSv1 +TLSv1.1 +TLSv1.2

(For CentOS 5)

SSLHonorCipherOrder On

SSLProtocol -All +TLSv1

Then restart Apache:

/etc/init.d/httpd restart

For testing, you can either perform an online query or run the following command from a CentOS server:

openssl s_client -connect www.DOMAIN.COM:443 -ssl3

The query result should not contain BEGIN CERTIFICATE.

To clear your computer’s DNS cache: Go to Start > Run, type “cmd” and press Enter. In the command prompt, type ipconfig /flushdns and run it to clear your DNS cache.

To clear browser history for the 3 most widely used browsers:

Internet Explorer

• Open Internet Explorer from Start menu > Programs.
• Press the “Ctrl + Shift + Delete” key combination.
• Select the files you want to delete and click the Delete button at the bottom.

Mozilla Firefox

• Open Mozilla Firefox from Start menu > Programs.
• Press the “Ctrl + Shift + Delete” key combination.
• Select the files you want to delete and click the Clear browsing data button.

Google Chrome

• Open Google Chrome from Start menu > Programs.
• Press the “Ctrl + Shift + Delete” key combination.
• In the window that appears, select the files you want to delete and click the Clear browsing data button. Additionally, Google Chrome allows you to delete files from a specific time range by selecting it from the “Obliterate the following items from” section.

There are certain commands frequently used for server management in Linux. With these commands, you can access and perform many basic operations on your server.

Basic Commands

pwd : prints the current directory you are in.

cd : used to navigate between directories. (Example: cd /home takes you to the /home directory.)

ls : lists all files and folders in the current directory. It has many parameters; type “man ls” for full details.

ls -l : produces a detailed list with date, file owner, and permissions.

ls -a : displays all files including hidden ones. Parameters can be combined. (Example: ls -la)

ls -lS : sorts files by size.

ls -lh : shows file sizes in MB, GB, TB.

ls -lt : sorts files by creation and modification date.

mkdir : used to create a new folder.

rm : used to delete files or folders. Type “man rm” for useful parameters.

touch : used to create a new file.

tail : shows the last output of a file. (Example: tail -20 /root/file.txt shows the last 20 lines.)

head : works opposite to tail, shows the first output of a file. (Example: head -10 /root/file.txt)

nano : file editing tool. Open with nano /root/file.txt, exit with CTRL + X.

service : used to start, query status, or stop services. (Example: service mysql restart)

ps : shows running applications. Most common usage: ps aux, which lists all running apps with CPU and RAM usage.

kill : terminates an application by its PID number. (Example: kill -9 PIDNUMBER)

killall : closes the specified application along with all its running instances.

who : displays users connected to the server.

uname : provides OS information. Use uname -a for kernel version.

df : shows disk usage. Most common: df -h, which displays in MB, GB, TB.

watch : continuously runs the command specified in quotes.

scp : transfers files via SFTP or sends commands to another SSH.

ftp : used for FTP connections and operations.

wget : used to fetch data from any URL.

passwd : used to change user password. If connected as root, you can change the root password.

man : displays parameters of commands.

reboot : restarts your server.

shutdown : used to completely shut down your server.

uptime : shows server uptime and load status.

tar : used for file compression or extraction. (Example: tar -zxvf to extract tar.gz, tar -cvf to compress)

unzip : extracts zip compressed files.

zip : compresses files into zip format.

gunzip : extracts gz compressed files.

Useful Operators

| : pipe character — used to combine two commands at once.

&& : runs the next command only if the first one succeeds.

; : runs the next command after the first one regardless of result.

grep : used for filtering, usually combined with pipe.

cut : used to cut data from command output.

sort : used to sort command outputs.

uniq : reporting command, used to statistically sort repeated items in output.

cat : prints file contents directly to screen.

more : helps read long command output more comfortably, used with pipe.

Examples

ls -la /home | grep netinternet

Filters files and folders in /home directory that contain “netinternet”.

ps aux | grep -v httpd

Shows all results from ps aux output except lines containing “httpd”.

cat /home/netinternet.txt

Prints the netinternet.txt file to screen.

date | cut -dE -f1

Cuts the output at the first occurrence of “E”: Thu Jul 18 00:36:15

cat test.txt | sort

Sorts all dates from smallest to largest.

cat test.txt | uniq -c

Prints repeated lines statistically.

cat /home/netinternet.txt;cat /home/net.txt

Performs two operations in a single line.

service mysql restart&&cat /home/netinternet.txt

If the first operation succeeds, the second command runs.

From the “Delivery Queue” section in your panel, you can view emails that you have sent but have not reached the recipient and are waiting in the queue. In this section, you can only see emails that recipient servers have not accepted. Recipient servers may reject your sent emails for various reasons. In this case, you need to contact the recipient server administrator to find out the source of the problem.

If there are many emails waiting in the queue and some are important to you, you can filter and display only the emails you want using the search options. Emails waiting in the queue are automatically resent at regular intervals. When the recipient server accepts the emails, the queued emails will be delivered. However, if you are aware of the resolution of the issue on the recipient server, you can also manually try to resend the emails.

This warning, seen in the upper right of WHM panel, appears when the automatic cPanel update fails.

Click the Details link to see the reason for the warning.

One of the warning reasons is that Microsoft® FrontPage® is no longer supported in new versions. We need to remove the FrontPage feature from the system.

Steps to remove it:

1- Go to WHM Panel >> FrontPage >> Uninstall FrontPage Extensions.
2- Check the “Uninstall Microsoft® FrontPage Extensions” checkbox.
3- Click the Uninstall button.

Now we can update cPanel. Find the Upgrade to Latest Version section in the WHM left menu and click the Click to Upgrade button. The process will take some time.

Another error may be that the MySQL version needs to be updated. MySQL 5.1 is no longer supported. You can upgrade to newer versions such as 5.5 or 5.6.

On servers with cPanel installed, the SSL certificate used for WHM, cPanel, or Webmail port access needs to be reset every year. A notification is sent to the server contact email address.

Your server’s SSL certificate for exim will expire in less than 30 days. You need to install a new certificate as soon as possible. You can install a new certificate using WHM’s “Manage Service SSL Certificates” interface.

Here are the steps to reset SSL certificates in WHM Panel:

• Log in to WHM panel.
• Click on Manage Service SSL Certificates in the left menu (you can use the search feature).
• On the page that opens, 4 services will be listed: Dovecot Mail Server, Exim (SMTP) Server, FTP Server, cPanel/WHM/Webmail Service.
• Click the Reset Certificate link on the right side of each service.
• Click the Proceed button in the popup.
• Click Proceed in the Restart cpsrvd window that appears next.
• This process needs to be done separately for each service.

Users experiencing locale problems on Ubuntu operating systems may encounter issues during the installation of software like PostgreSQL that requires locale settings.

perl: warning: Setting locale failed.

perl: warning: Please check that your locale settings:

    LANGUAGE = “en_US:en”,

    LC_ALL = (unset),

    …

    LANG = “en_US.UTF-8”

    are supported and installed on your system.

perl: warning: Falling back to the standard locale (“C”).

locale: Cannot set LC_ALL to default locale: No such file or directory

To solve this problem, add the export commands below to your bashrc or zshrc file. To apply without closing the SSH session, run the same commands directly in SSH once. However, adding them to bashrc or zshrc is important for the changes to persist.

export LC_CTYPE=en_US.UTF-8

export LC_ALL=en_US.UTF-8

Since bashrc is commonly used, running the following commands directly via SSH will be sufficient:

echo “export LC_CTYPE=en_US.UTF-8” >> ~/.bashrc

echo “export LC_ALL=en_US.UTF-8” >> ~/.bashrc

If you are using zsh, replace ~/.bashrc with ~/.zshrc in the commands above.