To check the health of a hard disk behind a 3Ware RAID card in Linux or UNIX, you can use the smartctl command. smartctl is a tool that provides information about the health of a hard disk and allows you to run SMART (Self-Monitoring, Analysis and Reporting Technology) tests. To check the health of a … Read more
To delete firewall rules in Linux, you can use the iptables command. iptables is a firewall service in Linux that allows you to configure and manage the firewall rules. To delete a specific firewall rule, you need to know the line number of the rule. You can use the iptables command with the -L option … Read more
To clear the mail queue in Sendmail, you can use the following command: sendmail -q The -q option tells Sendmail to process the mail queue and deliver any pending messages. By default, Sendmail checks the mail queue every hour, but you can use the -q option to force it to process the queue immediately. If … Read more
In Linux, you can find all the file descriptors used by a process by using the lsof command. The lsof (List Open Files) command lists information about files that are open by processes on a Linux system. To find all the file descriptors used by a specific process, you can use the following command: lsof … Read more
If you are encountering an issue where the yum command hangs on the message “Running transaction test,” it could be due to a variety of reasons, including network connectivity issues, a misconfigured repository, or a corrupted package database. Here are a few solutions you can try: Check network connectivity: Make sure that you have a … Read more
On a Dell server, desktop, or laptop running Linux, you can use the following command to find the service tag: sudo dmidecode -s system-serial-number This command will display the service tag of your Dell system by reading the system information from the DMI (Desktop Management Interface) table. The dmidecode command is a tool for dumping … Read more
If you are experiencing slow DNS resolution on a Linux system that has both IPv4 and IPv6 configured, there could be several reasons for the issue. Some possible causes and solutions include: Firewall rules: If your firewall is blocking DNS traffic, this could cause slow DNS resolution. To resolve this, you need to allow incoming … Read more
In the TCSH (also known as the C shell), you can check whether a directory is empty or not using the ls command and the test command. Here’s how: if ( ! (`ls -A $dir 2>/dev/null`) ) then echo “$dir is empty” else echo “$dir is not empty” endif In this example, the ls command … Read more
To save a file in Unix using the command line, you can use the vi editor. Here’s how: Open the vi editor: $ vi filename Replace filename with the name of the file you want to create. Press the i key to enter insert mode. Type or paste the content of the file. Press the … Read more
The “413 – Request Entity Too Large” error in Nginx occurs when a client tries to upload a file that is too large for Nginx to handle. This error can be solved by increasing the client_max_body_size directive in the Nginx configuration file. Here’s how: Open the Nginx configuration file: $ sudo nano /etc/nginx/nginx.conf Find the … Read more