Saturday, 16 July 2022

How to Resolve YUM Repo Mirror URLs List Issue on CentOS 8



Sometime mirror URLs does not work on CentOS 8 systems and gives the below error. To solve the yum repo issue need to replace it with base URLs.

Friday, 8 July 2022

How to Install Grafana Beta Monitoring tool on CentOS 7



Grafana is a power full software for real time system data monitoring also generate graph and dashboard for easy understanding. It is available in community and enterprise editions. Beta release can also installed via its separate repository. 

Wednesday, 6 July 2022

How to Install Grafana 9 Monitoring tool on CentOS 7



Grafana is a power full software for real time system data monitoring also generate graph and dashboard for easy understanding. It is available in community and enterprise editions.

Thursday, 30 June 2022

How to Install Spacewalk Server on CentOS 7



Spacewalk tool is a free and open source Linux operating system management tool for system provisioning and configuration/management/updating tool of its clients. It is a community version of Red Hat Satellite Server and widely used on Red Had derived distributions.

Tuesday, 29 March 2022

How to Enable Networking in Rescue Mode in CentOS 7



Sometimes required network connectivity in rescue mode to take server logs to other server/workstation for further analysis as the networking is not enabled during the initial rescue environment setup.

Sunday, 6 March 2022

How to disable consistent network device naming in CentOS 8



This article describes How to disable consistent network device naming in CentOS 8.

How to Configure Local Synced YUM repository on CentOS 7 using vsFTP



YUM (YellowDog Updater Modified) is a package management tool for RPM based Linux system that helps to install, uninstall, and update packages. Local yum repository is used to save bandwidth, fasten package installations, network installations and systems updates for n numbers of systems in a local area network.

Friday, 4 March 2022

How to Install and Configure Anonymous vsFTP Server on CentOS 7



vsFTP (Very Secure File Transfer Protocol) is a free and open source widely used client-server network protocol that used for transferring files between server and clients over the network.

How to Install FTP Client on CentOS 7



FTP (File Transfer Protocol) is a free and open source widely used client network protocol. It basically used to connect vsFTP server to upload/download files from server to client machine.

Tuesday, 1 March 2022

How to Extend a Logical Volume on CentOS 7



Sometime encountered with no space left on file system error and demand opened to increase file system space. It would be easy if file system is created under LVM.

How to Change or Rename a Regular Mount Point in CentOS 7



Sometimes mount point renaming require on a machine for any user request or any application requirements.

How to Configure Local Synced YUM repository on CentOS 7 using NGINX



YUM (YellowDog Updater Modified) is a package management tool for RPM based Linux system that helps to install, uninstall, and update packages. Local yum repository is used to save bandwidth, fasten package installations, network installations and systems updates for n numbers of systems in a local area network.

Friday, 25 February 2022

How to Allow/Deny Access for AD Users/Groups using Realmd on CentOS 8



Once the Linux machine joined with any Active Directory Domain, all the AD users can get SSH login on the machine with regular user privileges to avoid this access can manage using realm command.

Thursday, 24 February 2022

How to Resolve Slow SSH Login Before Getting Password Prompt on CentOS 8



Sometime SSH login failures encountered with gssapi-with-mic authentication method and hence takes time to get password prompt.

Wednesday, 23 February 2022

How to Allow SUDO Access to a Domain User/Group on CentOS 8



By default, Domain users doesn’t have any type of sudo privilege and even can’t switch as root user. On CentOS 8 sudo access can be granted access based on usernames or groups and same can be done for one/many commands.

Tuesday, 8 February 2022

How to Extend Logical Volume on CentOS 8



Sometime encountered with no space left on file system error and demand opened to increase file system space. It would be easy if file system is created under LVM.

Sunday, 30 January 2022

How to Install tcpdump and use of tcpdump command on CentOS 8



Tcpdump is a command line utility which is widely used to capture packet sniffer or filter TCP/IP packets that received or transferred over the network. it is allowing to analyse headers of TCP/IP which helps in network troubleshooting.

How to Configure Local Synced YUM repository on CentOS 7 using HTTP



YUM (YellowDog Updater Modified) is a package management tool for RPM based Linux system that helps to install, uninstall, and update packages. Local yum repository is used to save bandwidth, fasten package installations, network installations and systems updates for n numbers of systems in a local area network.

Sunday, 16 January 2022

How to Resolve showmount fails with error “clnt_create: RPC: Program not registered “on CentOS 7



NFS share is a network file sharing protocol. It is used to provide shared access to files and folders across Linux machines over the network. This error comes when sometime the NFS service is stopped on the NFS server and will gives the below error while running showmount –e <NFS Server IP>.

Saturday, 15 January 2022

How to Resolve kernel panic at boot with error initrd image file not found on CentOS 7



Sometime after yum update transaction break or kernel update or fresh install, the system fails to find initrd (initial ram disk) and also due to that unable to mount the root file system and also fail to boot the system with below message on CentOS 7 systems:

How to Resolve “kernel panic at boot with error Unable to mount root fs on unknown-block” on CentOS 7



Sometime after yum update transaction break or kernel update or fresh install, the system fails to mount the root file system and also fail to boot the system with below message on CentOS 7 systems:

Wednesday, 12 January 2022

How to Configure Local YUM repository on CentOS 7 using ISO Image



YUM (YellowDog Updater Modified) is a package management tool for RPM based Linux system that helps to install, uninstall, and update packages local and other client machines over the network. YUM resolve all dependency and install the package with all dependencies.

Tuesday, 11 January 2022

How to Install SEmanage on CentOS 8



SEmanage is a command-line utility and provide ability to manage SELinux contexts. Its needs separate installation by default this package is not available in CentOS 8 minimal installations.

How to resolve -bash: showmount: command not found on CentOS 8



showmount command: It is a command-line utility and provide ability to manage NFS share. Its needs separate installation by default this package is not available in CentOS 8 minimal.

How to Resolve wrong fs type while mounting NFS share on CentOS 7



NFS share is a network file sharing protocol. It is used to provide shared access to files and folders across Linux machines over the network. This error comes when the nfs-utils package is missing from the machine and will give the below error while mounting any NFS share point.

Tuesday, 4 January 2022

How to resolve -bash netstat command not found on CentOS 8



Netstat is a command-line utility and provide ability to check open ports whether it is UDP or TCP. Its needs to separate installation by default this package is not available in CentOS 8 minimal.

How to Change the SSH Port on CentOS 8



We can change the default SSH port CentOS 8 as an added security concerns. To Change the SSH Port on CentOS 8 systems connect to server with root privileges.

How to resolve -bash: semanage: command not found on CentOS 8



Semanage command: It is a command-line utility and provide ability to manage SELinux contexts. Its needs to separate installation by default this package is not available in CentOS 8 minimal.

How to Install and Use tcpdump Command on CentOS 8



Tcpdump is a command line packet sniffer/ packet analyser tool which used to capture or filter TCP/IP packets that received or transferred over a network on a specific interface. By default, tcpdump is available under most of Linux distributions but if we have a minimal installation of CentOS 8.

Saturday, 1 January 2022

How to Disable SSH Remote Root Login on CentOS 8



After fresh system installation the Remote root login is enabled by default on the CentOS 8. As recommended, SSH Remote root login must be disabled for security and compliance on production systems.

How to Enable SSH root login on CentOS Stream 9 System



After fresh system installation the root login on the CentOS Stream 9 is disabled by default. When attempt to login as root user to CentOS Stream 9 the access will be denied (access denied).

How to Install CentOS Stream 9 Minimal Step by Step



The CentOS Project is recently released CentOS Stream 9. It is a new community version of RHEL and added many new features for users.