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• How to set timezone on RHEL Linux Host from RHEL 7 onwards ? February 22, 2024
• Solved: root is not allowed to run sudo on ngelinux. This incident will be reported. January 5, 2024
• How to reinstall an installed package using YUM/DNF in linux ? December 26, 2023
• How to remove a directory “-p” in Linux ? December 12, 2023
• Solved: ERROR: Could not create or update ‘/usr/local/nagios/var/nagios.configtest’ October 5, 2023
• How to extract private key- encrypted or decrypted from PFX certificate file ? September 22, 2023
• Solved: Nagios: qh: Failed to init socket ‘/usr/local/nagios/var/rw/nagios.qh’. bind() failed: September 11, 2023
• Solved: ndo2db: Could not bind socket: Address already in use. September 7, 2023
• Solved: cannot find -lboost_system-mt. September 7, 2023
• How to stop NetworkManager service to modify resolv.conf file ? August 23, 2023
• Solved: SWEET32 Issue, CVE-2016-2183. Check TLS1.0 and disable it in Configuration on Linux. August 21, 2023
• How to see if hyper threading or Multi threading is enabled on Linux or not from OS perspective ? August 20, 2023
• Solved: Determine which password-hash support is available on Linux. August 1, 2023
• Configure NFS v4 only server in RHEL/Centos 8. Is it possible on RHEL 6 and RHEL 7 ? July 19, 2023
• Solved: Disable core generation on a Linux system for all users: RHEL 6,7,8. July 11, 2023
• Solved: su: failed to execute /bin/ksh: Resource temporarily unavailable ? July 11, 2023
• How to identify which nvidia card is available on Linux ? July 5, 2023
• How to change default kernel version boot order in RHEL 8 ? June 22, 2023
• Solved: ntpd[]: frequency file /etc/ntp/ntp.drift.TEMP: Permission denied. March 29, 2023
• Solved: ssh error no hostkey alg in Linux in RHEL 9 and in older versions. March 29, 2023
• How to install GNOME desktop in Linux: CentOS/RHEL ? March 24, 2023
• Solved: RHEL/CentOS: Could not import the lzma module. Your installed Python is incomplete. March 24, 2023
• How to increase tmpfs filesystem in Linux ? March 23, 2023
• Search through a word till end of line with sed in Linux Bash Shell. January 18, 2023
• How to send email to multiple recipients in mailx command ? January 17, 2023
• How to record complete Linux session/terminal logs to a file ? January 4, 2023
• How to remove all files including hidden files in Linux ? January 3, 2023
• Solved: ERROR 1045 (28000): Access denied for user ‘dbuser’@’localhost’. December 22, 2022
• Different ways to Reset user password in Mariadb mysql. December 22, 2022
• How to troubleshoot httpd service failing in Linux ? December 17, 2022
• How to encrypt bash shell script in Linux ? December 16, 2022
• Solved: kernel: spectre[]: segfault at ip sp error 4 in spectre ? December 10, 2022
• Solved: insights-client: ConnectionError: (‘Connection aborted.’, error(110, ‘Connection timed out’)). December 9, 2022
• How to compare rpm packages on two servers and find missing packages ? December 8, 2022
• Solved: TERM environment variable not set during scp. December 5, 2022
• Solved/Way forward: cat: grub.conf: Permission denied. November 30, 2022
• How to configure and install Nagios Server on Linux ? November 27, 2022
• How to check BIOS version/information in Linux ? November 12, 2022
• How to edit and add a new user or samba share in Solaris 10 ? November 5, 2022
• How to install OCI extension in Linux for PHP? November 1, 2022
• How to install Konsole 5 in RHEL 8 or CentOS 8 ? November 1, 2022
• How to check open ports in Linux using nc, telnet and curl command ? October 14, 2022
• Solved: Unit rpcbind.service has failed. September 30, 2022
• Solved: Not able to create VNC session in working state on Debian machine ? September 30, 2022
• Solved: xmobar package dependencies: Steps to Install xmobar on Linux: RHEL 7. September 20, 2022
• How to get the last field of a string using cut command in bash linux ? September 20, 2022
• Solved: nrpe[]: Host 172.23.99.999 is not allowed to talk to us! September 15, 2022
• Solved: Chronyc NTP error on RHEL for not syncing time ? September 12, 2022
• How to install TCL 8.6 and TK 8.6 in Linux- The easiest way ? September 5, 2022
• How to setup nagios server on Linux ? September 3, 2022
• Tru64 Command CheatSheet September 3, 2022
• How to use and setup pip server path to get the packages ? September 3, 2022
• Copy shell script and execute it using Ansible. September 3, 2022
• Ansible commands cheatsheet September 3, 2022
• How to run a command with root user in Ansible ? September 3, 2022
• Ansible playbook to create logical volumes under LVM on Redhat or CentOS linux. September 3, 2022
• Adding new disk/LUN under multipath Linux mpath. September 3, 2022
• Steps to remove clone from Veritas Volume Diskgroup ? September 3, 2022
• Steps for Disk replacement in IBM ESS. September 3, 2022
• Ansible playbook to install list of packages on Redhat or CentOS Linux post OS install. September 3, 2022
• Analyzing crash dump or vmcore file in linux step by step. September 2, 2022
• Solved: ln: failed to create hard link: Operation not permitted in Linux. September 2, 2022
• How to check and install redcloak service on Linux ? September 2, 2022
• Solved: VCS CRITICAL V-16-1-10037 VxFEN driver not configured. Retrying… September 2, 2022
• Things to check in case of X11 Forwarding Issues. September 2, 2022
• Solved: bosboot error: 0516-602 lslv: Logical volume name not entered. September 2, 2022
• How to solve in.mpathd[-]: [ID –daemon.error] NIC failure detected on vnet1 of group bond0 ? September 2, 2022
• How to build and install openssl 1.1.1 on any Linux System – Example on RHEL 7 ? September 2, 2022
• Solved: error while loading shared libraries: libssl.so.1.1: cannot open shared object file: No such file or directory September 2, 2022
• How to get FSPDUMP from an HMC following a call home event (possible HW failure) ? September 1, 2022
• Steps to reset an ilo password on Linux using hponcfg. September 1, 2022
• NTP Trouble Shooting in Linux/AIX/Solaris/Tru64 OS. August 31, 2022
• How to update Firefox to Support TLS 1.1+ in RHEL/CentOS 5/6/7 ? August 31, 2022
• How to install and verify the Helvetica fonts in RHEL 8 ? August 31, 2022
• How to generate X server config file to enable high resolution modes ? August 31, 2022
• How to clear a specific vixen license slot ? August 31, 2022
• How to reset or cleanup the device tree on an AIX server? August 31, 2022
• How to restart DCS SIS agent service: SCSP agent on Unix system ? August 31, 2022
• How to Install Python cx_Oracle module on Unix/AIX Server. August 30, 2022
• How to extend multipath mpath disk in Linux ? August 30, 2022
• How to solve “Lowest Stratum not being used for Current Time Source.” ? August 28, 2022
• How to place html file in docker webserver and push it to Google Container Registry(GCR) in GCP ? August 28, 2022
• Solved: modprobe: FATAL: Module nvidia is in use. August 28, 2022
• Solution: Pstack error: crawl: Input/output error ? August 27, 2022
• Process of nvidia driver installation on x86_64 Linux. August 26, 2022
• How to view LDAP maps from a client machine ? August 26, 2022
• How to check Chronyc clock and sync our system clock ? August 26, 2022
• Solved: Repodata is over 2 weeks old ? August 8, 2022
• Solved: How to address Redhat Bug polkit using high cpu in Linux ? August 7, 2022
• How to install Jenkins on RHEL or CentOS ? August 7, 2022
• Solved kernel: nfs: Unknown parameter ‘noquota’. July 29, 2022
• How to see available VGA/GPU/OpenGL/Displays available on our Linux Server ? July 29, 2022
• Solved: kernel: INFO: task df:147233 blocked for more than 120 seconds. July 29, 2022
• Solved: httpd[]: Unknown Authn provider: ldap in Linux. July 17, 2022
• How to download a package using YUM in Linux ? July 17, 2022
• Steps to install Ansible on RHEL 6 or CentOS 6. July 15, 2022
• How to check if time is synced fine with NTP server in linux ? July 11, 2022
• How to download package on my linux machine ? July 11, 2022
• How to pick complete line while working in Loop under Unix or Linux ? July 1, 2022
• Trick to resolve High memory issue on Linux or Unix Server. June 30, 2022
• How to test log rotation script after its modification – logrotate config in linux ? June 30, 2022
• How to sort with memory/CPU in top command in Linux or Unix? June 24, 2022
• Solved: kernel:NMI watchdog: BUG: soft lockup – CPU#20 stuck for 22s! [: ? June 24, 2022
• How to enable compat mode on passwd map in Linux ? June 24, 2022
• How to install XLC Compiler on IBM AIX server ? June 23, 2022
• How to install glibc package version 2.28+ on RHEL 7 unofficially for testing purposes? June 22, 2022
• Meaning of TCP full window messages and what needs to be checked in this case ? June 22, 2022
• How to add your ID as admin in nagios ? June 22, 2022
• How to enable epel repository on RHEL/CentOS 6.x versions ? June 22, 2022
• How to get console IP details from linux server via IPMI ? June 22, 2022
• Solved: bind_ldap_simple: lookup(ldap): Unable to bind to the LDAP server: (default), error Can’t contact LDAP server. June 21, 2022
• Why we are not able to change open files to unlimited in Linux ? June 21, 2022
• How to install dnsperf on RHEL 6/Centos 6 and use this to test DNS server ? June 16, 2022
• Solved: sudo taking a lot of time, system responding very slow. June 16, 2022
• How to change swappiness on a linux server ? June 15, 2022
• How to clear system page and buffer cache daily on linux server ? June 15, 2022
• Installing dnsperf tool on RHEL or CentOS 7. June 10, 2022
• Steps to install PostgreSQL version 14 on centos 7 ? May 31, 2022
• How to stop pacct daemon/service and stop its loggging in Linux ? May 31, 2022
• How to check for open port in Linux on multiple servers together ? May 27, 2022
• See how to set ulimits quickly on Linux server for whole system and for individual user. May 26, 2022
• Solved: Connection to server closed by remote host, idle timeout occurring on linux server ? May 24, 2022
• Solved: Warning: Qt Warning: QStandardPaths: XDG_RUNTIME_DIR points to non-existing path ‘/run/user/44564’, please create it with 0700 permissions. May 22, 2022
• Interesting Tip: Know how to create an infinite link in Linux ? May 22, 2022
• Steps to Check and install package on Debian OS. May 22, 2022
• Solved: libreoffice error application can’t be started, user installation not complete. May 22, 2022
• How to add certificate file and its key on httpd server database in Linux ? May 22, 2022
• How to track where umount: /custom: target is busy ? May 21, 2022
• Solved: [error] Unable to obtain semaphore. May 21, 2022
• How to check and correct the hardware clock of the Linux System ? May 15, 2022
• Searching and installing package on SLES – Suse Enterprise Linux ? May 15, 2022
• Solved: chgrp: changing group of `testfile’: Operation not permitted. How to solve NFS 16 group limit ? May 15, 2022
• Identify CPU clock speed when its not visible under different commands like lscpu ? May 15, 2022
• Solved: cron jobs stopped working automatically ? May 15, 2022
• How to add a custom file in log rotation in linux ? May 14, 2022
• How to check the IP address on linux machine if no ifconfig command is installed ? May 1, 2022
• How to set maximum user processes in Linux ? April 29, 2022
• Solved: Error with swapon: swapon failed: Invalid argument. April 29, 2022
• How to increase swap by creating a file in Linux ? April 29, 2022
• How to check and update new font in Centos/Redhat Linux ? April 29, 2022
• Steps to upgrade java on Linux/AIX/Unix Production Servers. April 5, 2022
• Steps to patch Linux/RHEL server. April 5, 2022
• AIX: How to take console of LPAR from HMC ? April 5, 2022
• Solved: Samba share not accessible – Error NT_STATUS_NO_TRUST_SAM_ACCOUNT ? April 5, 2022
• Solved: Veritas Cluster group is not starting on two nodes as expected. April 5, 2022
• How to Raise a SR to Oracle for failed TSM drive ? April 2, 2022
• dos2unix Script: How to convert DOS text into Unix text ? April 2, 2022
• Solved: How to get rid of password prompt when running Veritas commands. March 23, 2022
• How to solve “Unable to negotiate with port <##>: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1″ ? March 14, 2022
• Solved: VCS NOTICE V-16-1-50862 Unable to online group -groupname- on system ngeaix001. Group is autodisabled. March 14, 2022
• Solved: IBM AIX: “ntpq: read: A remote host refused an attempted connect operation.” March 10, 2022
• NTP Issue: How to solve “No Current Time Source.”? March 10, 2022
• How to check what all users are logged into my Linux server ? March 7, 2022
• NTP Issue: How to solve “NTP Syncing against LOCAL.”error ? March 1, 2022
• How to check when Linux kernel is updated on server ? March 1, 2022
• Solved: NFS shares are not visible on the NFS client ? February 16, 2022
• NTP Issue: How to solve “Stratum 16 Sources Exist.” ? February 3, 2022
• Solved: /var/cache/pulp getting full 100% ? January 28, 2022
• Solved: How to clean /var/spool/squid logs on Redhat Satellite server ? January 28, 2022
• Solved: Error: PLP0000: Redhat Satellite Pulp Issue ? January 28, 2022
• How to unlock user in IBM AIX server ? January 25, 2022
• Part 1: Introduction to Openstack: What is openstack ? January 24, 2022
• How to solve kernel panic error : Kernel panic – not syncing: VFS: Unable to mount root fs on unknown-block(0,0)? January 20, 2022
• Solved: Error: Unable to negotiate with — port 22: no matching host key type found. Their offer: ssh-dss ? January 19, 2022
• How to boot from RHEL ISO on HP ILO CLI to recover a server ? January 19, 2022
• How to stop/start DB on RAC Cluster Node ? January 8, 2022
• Part 17: GCP: Docker: How to deploy a web server with a single command ? January 8, 2022
• Part 16: GCP/Kubernetes: Hands on with kubernetes Cluster. January 7, 2022
• Part 15: GCP: Deploying a Kubernetes Cluster with Google Kubernetes engine. January 7, 2022
• How to restart VIP resource in Oracle RAC Cluster ? January 6, 2022
• How to Replace a Disk in the ZFS Root Pool ? January 4, 2022
• GCP: How to disable billing on a project in Google Cloud Platform ? January 3, 2022
• Not able to ping a server from an IBM AIX server – Know how to clear DNS cache. January 3, 2022
• Part 14: GCP: How to create docker container in GCP ? December 30, 2021
• Part 13: GCP: How to create a Windows VM, set its Admin password, and connect to it via RDP ? December 24, 2021
• Part 12: How to make IP address of any VM/Application static on GCP ? December 24, 2021
• Part 11: GCP: How to deploy a wordpress blog on GCP ? December 23, 2021
• Part 10: GCP: How to keep disk intact even after deleting VM in GCP ? December 23, 2021
• How to share a NFS partition temporarily to a specific host in AIX ? December 17, 2021
• Part 9: GCP: GCP Infrastructure December 16, 2021
• Part 8: AWS vs Azure vs GCP Comparision. December 14, 2021
• Part 7: GCP: Creating Storage Bucket. December 13, 2021
• Part 6: GCP: Hands on with containers: Creating VM. December 10, 2021
• Part 5: GCP: Register with Google Cloud Platform. December 10, 2021
• Part 4: GCP: Why to use Google Cloud Platform ? December 10, 2021
• Part 3: GCP: What is GCP ? December 9, 2021
• Part 2: GCP: Different uses of Cloud Computing ? December 9, 2021
• Part I. GCP – What is Cloud Computing ? December 9, 2021
• How to clear and bring a disk into ASM on IBM AIX ? December 7, 2021
• Solved: AIX: Unable to read either superblock. December 1, 2021
• How to clear fmadm faults on Solaris server ? November 25, 2021
• How to verify if all services are running fine on Redhat Satellite Server ? November 18, 2021
• How to increase disk space on a virtual Linux server hosted on VSphere ? November 17, 2021
• RHEL or Centos Linux: Kdump generated manually however not able to find it on reboot ? November 17, 2021
• How to clear and start a faulted or partial service group in VCS ? November 16, 2021
• How to mount a NFS share permanently in IBM AIX ? October 28, 2021
• Solved: passwd: Libuser error at line: 425 – Error removing stale lock `/etc/passwd.lock’: Permission denied. October 27, 2021
• How to increase swap/pagefile size in IBM AIX server ? October 27, 2021
• Quick Way to easily see memory, cpu, and swap usage in AIX ? October 26, 2021
• How to prevent users from saving/accessing certain files on a samba share in Linux ? October 26, 2021
• Solved: VCS WARNING V-16-1-50104 Command failed. At least Group Operator privilege required. September 28, 2021
• Difference between RHEL 7 and RHEL 8 ? September 27, 2021
• How to remove a LV(logical volume) in an AIX server ? September 27, 2021
• Understanding /etc/fstab file and its dump option. Is it of any significance ? September 14, 2021
• How to analyze memory in kernel crash dump on linux ? September 1, 2021
• Linux/AIX: How to grant sudo commands with options access to a user ? September 1, 2021
• How to gzip a file to a seperate location in linux ? August 27, 2021
• Solved: Identify which filesystem causing df command to hang on linux ? August 27, 2021
• How to print all columns except first column in Linux bash shell ? August 13, 2021
• How to replace ESS MMV Disk in case of faulty disk ? August 1, 2021
• How to remove all emergency fixes from IBM AIX server in one go ? July 20, 2021
• What is the maximum file name length in linux and how to see this ? Is this really 255 characters ? July 12, 2021
• How to print a sequence of 100 numbers using shell script or bash shell while loop ? July 12, 2021
• How to create a new Filesystem in IBM AIX server ? July 9, 2021
• How to extend veritas filesystem on IBM AIX/Linux ? July 9, 2021
• How to see status of all disk arrays on HP Proliant Servers ? July 9, 2021
• How to check if a NFS server is reachable from NFS client ? July 9, 2021
• Solved: Why Linux Server rebooted when all LUN paths failed ? July 9, 2021
• How to extend LV on RHEL/CentOS with a single command on live systems ? July 8, 2021
• How to verify if hung_task_panic kernel parameter is working properly on linux ? July 8, 2021
• What is hung task and how to panic our RHEL/centos system when a task remains hanged for specific period of time ? July 8, 2021
• Solved: rhel7 useradd[12345]: cannot open login definitions ? July 6, 2021
• What is the use of dmesg file, and how is it different from messages log file ? July 5, 2021
• How to grep some content with before and after lines in linux and AIX ? June 30, 2021
• How to control FTP user/system access on an IBM AIX system ? June 28, 2021
• How to reboot an IBM AIX server, RHEL Server, and Solaris host ? June 28, 2021
• TCPDump useful examples for day to day tasks for RHEL/CentOS. June 26, 2021
• Find files modified before 15 days in current directory and delete them. June 14, 2021
• RHEL 7: How to use journalctl to examine system logs and its various options ? June 11, 2021
• Check Journalctl Log size and archive/delete old logs. June 11, 2021
• How to promote new version of a Content View in Redhat Satellite 6.5 ? June 10, 2021
• Solved: Satellite Certificate has expired error 3006 code on Redhat Satellite 6.5. June 10, 2021
• How to sync repository in Redhat Satellite 6.5 ? June 10, 2021
• RHEL/Centos: How to add CPU governors and change CPU frequency on servers ? June 10, 2021
• Systemctl : RHEL 7: How to check, start, stop, and manage units/services ? June 10, 2021
• How to install a specific version of RPM from different versions using YUM ? June 9, 2021
• How to monitor IP Tables changes in Linux ? June 9, 2021
• How to list all services on RHEL 6 and RHEL 7 ? June 9, 2021
• Introduction to IBM AIX OS ? June 7, 2021
• How to collect pdump in AIX ? June 6, 2021
• How to see serial number in IBM AIX OS ? June 6, 2021
• How to fix: sosreport: No space left on device error ? June 6, 2021
• Solved: 0516-787 extendlv: Maximum allocation for logical volume XXYY ? June 6, 2021
• How to get HBA card version/driver details in Linux RHEL6/7 ? May 18, 2021
• How to copy partition table details from one drive to another in Linux ? May 17, 2021
• How to get root cause of server reboot in IBM AIX ? May 11, 2021
• How to change disk parameter in AIX ? May 11, 2021
• How to republish a repository from Satellite 6.5 CLI ? March 17, 2021
• How to resolve NFS stale file handle issue in linux ? March 17, 2021
• How to download redhat rpms from redhat support ? March 17, 2021
• How to enable a repository in Redhat Satellite 6 client host ? March 17, 2021
• Solved: Redhat Satellite Subscription error: Unable to find available subscriptions for all your installed products. March 17, 2021
• Solved: ERROR: E: Failed to install /usr/sbin/eject during RPM installation. March 17, 2021
• AIX: Solved: gencore:: Not owner March 17, 2021
• Solved: subscription-manager – Not supported by a valid subscription. March 17, 2021
• What logs to provide to IBM for any AIX crash? March 17, 2021
• How to see product version of IBM AIX OS ? March 17, 2021
• How to get HMC IP address from the LPAR in AIX ? March 17, 2021
• How to increase LP count in AIX filesystem ? March 17, 2021
• How to increase filesystem/logical volume in AIX ? February 17, 2021
• How to check which process is using a port in AIX ? February 16, 2021
• Easiest way to get the dates when your redhat linux server is patched. February 15, 2021
• How to correct bosboot error messages in AIX ? February 15, 2021
• How to rebuild RPM DB on Linux ? December 8, 2020
• How to see Kernel Package level on Solaris 10 and Solaris 11 ? September 18, 2020
• Check ping response from a list of servers using for loop in Unix/Linux ? September 18, 2020
• How to register for Red Hat Support Login ? September 18, 2020
• How to see system error messages in AIX ? September 18, 2020
• How to colllect and send data to Oracle for any Solaris Hardware Issue ? September 18, 2020
• How to enable I/O Completion Ports in AIX ? September 15, 2020
• Solved: A specific user is not able to see usage statistics in “df” command output ? September 15, 2020
• Solved: nfsmnthelp: 1831-019 host2: System call error number -1. September 14, 2020
• Solved: DNS Issue: How to deal with RFC 1918 response from Internet for X.X.XX.XXX.in-addr.arpa warning messages ? May 7, 2020
• How to create full size one partition using parted command in Linux ? April 5, 2020
• How to create logical drive in HP Smart Storage Array Configuration CLI hpssacli ? April 5, 2020
• AIX: Korn Shell: How to set tab auto completion and hostname, present working directory path in the terminal(PS1 Variable) ? April 5, 2020
• AIX: How to get top 15 Processes using high swap usage. April 5, 2020
• How to turn on multithreading in AIX server ? April 5, 2020
• AIX: How to set full core generation. April 5, 2020
• Solved Error: Required file .//source/crs/Disk1/rootpre/pw-syscall32 is missing during OHS install. April 5, 2020
• How to get network address of fibre channels and scan new storage in AIX ? April 4, 2020
• Solved: CRS-4995: The command ‘Start resource’ is invalid in crsctl. Use srvctl for this command. April 4, 2020
• Solved: /var/adm/messages and auth.log file not rotating in Linux. April 4, 2020
• How to setup port forwarding to login on a host via Jump server via putty ? April 3, 2020
• How to change user password expiry date to never expiry in Linux ? April 3, 2020
• How to correct missing disk issue in AIX ? February 23, 2020
• LVM Solutions: How to change a faulty hard drive in Redhat/Centos Linux on production server ? December 3, 2019
• How to write random or zero characters to a device in Linux ? November 26, 2019
• How to delete an array & its content in HPSSACLI or HP Smart Storage interface ? November 26, 2019
• How to add Yubikey to ssh agent in Linux or Mac OS ? November 26, 2019
• How to work on multiple servers together in a single time ? November 26, 2019
• How to re-enable logical drive or disk in HP Prolient Servers ? November 26, 2019
• How to delete logical drive in HP Smart Storage Administrator ? November 26, 2019
• Solved: libvirt: Storage Driver error : internal error: storage volume name ‘XXX.ngelinux.com_disk1.qcow2’ already in use. November 26, 2019
• Solved: Not able to see console after POST in Redhat Enterprise Linux or Centos. November 26, 2019
• systemd limit directives: Set ulimit in RHEL7 or CentOS 7 November 22, 2019
• How to reset TIME_WAIT connection on my linux server ? November 22, 2019
• How to use hponcfg tool in Linux to reset ILO password ? November 22, 2019
• How to reduce XFS filesystem on Redhat Enterprise Linux or CentOS ? November 20, 2019
• How to view last users’ login history in Linux ? November 5, 2019
• Meaning of the value stored in /proc/sys/kernel/panic file ? November 5, 2019
• What is force umount and lazy umount in Linux and which option we should use ? November 5, 2019
• How to identify if our linux kernel is build with a specific option or not, for example if cgroup option is enabled during kernel build or not ? September 21, 2019
• What is the meaning and impact of /run/user/0 and /run/user/1000 directories in Linux(Fedora) ? September 21, 2019
• How to run sudo command over ssh to remote servers via a script in Linux/Unix ? September 21, 2019
• How to identify /dev/mapper/path actual device on our linux system ? August 24, 2019
• How to compare timestamp of a logfile and generate error in case its 72 hours old ? August 6, 2019
• What is entropy pool in linux and how to generate and see the entropy pool data ? August 4, 2019
• Python Ping Script: Ping a list of hosts/servers from a file in python ? July 11, 2019
• What is the meaning of 0 in /proc/sys/kernel/ctrl-alt-del file in Linux ? July 11, 2019
• How to check ping status of a domain/host name in python ? July 11, 2019
• Explanation of /etc/prelink.cache & prelink.conf file : What is prelink cache in Linux ? June 24, 2019
• How to turn off bell sound during TAB completion in linux ? June 24, 2019
• How to take dump or backup of all mysql databases in Linux ? June 24, 2019
• Solved: lastb command not working or utmp file not updating. June 2, 2019
• How to view current logged in users in linux ? June 2, 2019
• How to view, setup and analyze sshd(Secure shell daemon) logs in redhat or centos linux ? May 31, 2019
• How to kill or clean zombie or defunct processes in linux ? May 31, 2019
• How to reverse file content using sed command ? May 20, 2019
• What is character class in bash shell linux and how to use them to search a pattern ? May 20, 2019
• Different ways/commands to look for IP address of your Linux Machine ? May 20, 2019
• Different ways to create a file in Linux ? May 20, 2019
• Use of set and unset command in linux bash shell. May 20, 2019
• How to make variables as read only in bash shell linux ? May 20, 2019
• Solved: Error on Linux -bash: /usr/bin/chmod: Permission denied. May 20, 2019
• How to update RHEL, or centos major release version: from RHEL 5 to RHEL 6, or from RHEL6 to RHEL 7 ? May 14, 2019
• What is IFS in linux bash shell ? May 14, 2019
• How to color a text/string in linux bash shell & make it blink ? May 13, 2019
• What are different types of positional parameters available in linux ? May 13, 2019
• How to mount a filesystem from backup superblock location ? May 12, 2019
• How to search and replace text where line contains some specific string in Linux shell ? May 12, 2019
• Regex to look for multiple characters or words in linux bash shell ? May 12, 2019
• Use of dot “.” in regular expressions during search/grep in bash shell linux ? May 12, 2019
• How to get length of a string/integer variable in linux bash shell ? May 12, 2019
• How to unset variables in linux bash shell (normal and read only variables) ? May 12, 2019
• How to look/grep for special characters in a file in linux bash shell ? May 12, 2019
• What are the default link count of a new directory or file in linux bash shell ? May 11, 2019
• How to remove empty lines from a file in bash shell linux ? May 11, 2019
• How to test a valid IP address in Linux Bash Shell ? May 11, 2019
• Tip: How to quickly fill whole disk space in Linux with one command ? April 25, 2019
• Different ways to keep a process running even after ssh logout or session/terminal is closed in linux ? April 25, 2019
• Different ways to clear screen in Linux ? April 24, 2019
• Different ways to get an owner of a file in Linux ? April 24, 2019
• How to find filesystem block size in linux or Unix ? April 22, 2019
• How to debug SSL Certificate issue(s) with a host in linux: openssl utility ? April 22, 2019
• How to add a different username in ssh config for remote server ssh to save our time ? April 16, 2019
• Easy to understand : How to efficiently use screen command and multiplex your terminal session ? April 12, 2019
• How to get active connections on a particular port in Linux ? April 10, 2019
• How to get services listening to a particular port in Linux ? April 10, 2019
• How to copy files and keep it in sync using rsync command in Linux ? April 7, 2019
• Linux: How to redirect command output to a file and also view it on screen side by side ? April 6, 2019
• RHEL or Centos: How to count number of files inside a directory in Linux ? April 6, 2019
• RHEL or CentOS Linux: How to read a file with spaces in its name ? April 6, 2019
• Redhat/CentOS/Generic Linux: How to sort files by their size ? April 6, 2019
• How to view IPv6 IP address and ping it on Linux ? April 6, 2019
• Use of shebang #!/bin/bash in Linux shell scripts. April 4, 2019
• Linux Redhat/Centos/Debian: How to list files sorted by date/time ? April 3, 2019
• Linux: How to Find files modified in last few minutes or hours or days ? April 3, 2019
• How to increase ext3/ext4 disk partition in Linux, which is not on LVM ? April 1, 2019
• RHEL 7 or CentOS 7: How to work with XFS filesystem: Backup/Restore/Create/Extend Operations ? March 25, 2019
• Solved: xfs_quota: cannot set limits: Function not implemented. March 25, 2019
• RHEL 7 or CentOS 7: How to view file extent information for XFS filesystem ? March 18, 2019
• Introduction to Systemd, how to start using systemd in RHEL 7 or Centos 7 ? March 13, 2019
• Why journalctl logs disappear after reboot and how to make it permanent ? March 13, 2019
• What are control groups in RHEL or CentOS 7 and how to view different cgroups ? March 9, 2019
• How to list, stop, start, manage services in Centos or Redhat Linux 6 and 7 ? March 6, 2019
• How to create, list, delete alias or aliases in Redhat or Centos Linux ? March 5, 2019
• How to pass multiple keystrokes or y to a command in Centos or Redhat Linux ? February 22, 2019
• How to freeze and unfreeze your linux bash shell terminal ? February 22, 2019
• Brief explanation how to read compressed log files in Centos or Redhat Linux. February 22, 2019
• Tip: sudo in the last command in Linux bash shell quickly. February 22, 2019
• Docker Basic Tips 1: How to download an image and work with containers ? February 6, 2019
• DNS Server in Linux : Setup, Configuration and Interview Tips February 6, 2019
• Character, integer, string variables manipulation in Python February 2, 2019
• Examples of List usage in Python. February 2, 2019
• Dictionaries in Python February 2, 2019
• While/For Loop & Single/Multi-line comments in python. February 1, 2019
• Lists in Python February 1, 2019
• Tuples in python February 1, 2019
• Error handling in python. February 1, 2019
• How to create functions in python: Get square of a number. January 30, 2019
• How to get maximum of 3 numbers : Usage of if elif and else in Python. January 30, 2019
• How to import math library in Python and call its functions ? January 28, 2019
• How to take backup of docker container ? January 17, 2019
• Docker: How to save images & containers in a tar file and restore them on different machine ? January 16, 2019
• Part 6: Deploy LAMP Server with phpmyadmin using docker_compose file. January 15, 2019
• Part 5: Deployment of Container through Docker Compose File January 14, 2019
• Solved: ERROR: Version in “./docker-compose.yml” is invalid & found character ‘\t’ that cannot start any token January 14, 2019
• Docker: How to ssh into a docker machine with IP ? January 14, 2019
• Part 4: Docker Machine, Swarm Introduction and implementation January 14, 2019
• Solved: Unable to query docker version: Get https://192.168.99.100:2376/v1.15/version: x509: certificate is valid for 192.168.99.103, not 192.168.99.100 January 11, 2019
• Part 3: Docker Compose File: Working with Multiple containers January 10, 2019
• Solved: NameError: name ‘_name_’ is not defined in docker python program January 10, 2019
• Boot process of Linux in brief. January 9, 2019
• Solved Error : docker-machine ls command asking for password. January 8, 2019
• Part 2: Docker – Mounting Local Storage with Container : Working with Volumes & Pushing image to Docker Hub January 8, 2019
• Part1: Docker Introduction: How to start with docker ? January 7, 2019
• Explanation of Firewalld in Linux RHEL 7, or Centos 7 and how to work with it. December 23, 2018
• Explanation of IP Tables in Red hat Linux or CentOS ? December 22, 2018
• Introduction of SCSI, iSCSI, and SAS in Linux and which is better. December 20, 2018
• NIS Server in RHEL/CentOS Linux – Installation, Configuration, Interview Questions, & Tips December 19, 2018
• DHCP Server in Linux(RHEL or CentOS) – Installation, Configuration, Interview Questions, Tips December 18, 2018
• NFS(Network File System) Server in Linux – Installation, Configuration, Interview Questions for Redhat/Centos December 17, 2018
• syslog, rsyslog, syslog-ng Description and Usage in Linux December 12, 2018
• 4th Ansible YML Playbook: Copy a script and run on remote server. December 11, 2018
• Third Ansible playbook introducing usage of copy module, tags, and how to disable gather facts step. December 10, 2018
• How to run ansible playbook on a single or multiple selected host(s) ? December 10, 2018
• How to do syntax check of yml or ansible playbook file ? December 10, 2018
• First YAML Script: Ansible playbook to ping all hosts in the list. December 6, 2018
• YAML Script: Second ansible playbook to get date and server uptime status. December 5, 2018
• First configuration after ansible install before creating YML scripts. December 4, 2018
• Difference between bonding and teaming in Linux ? December 4, 2018
• Configure OOM Killer in Linux. December 1, 2018
• What is low and high memory in Linux ? November 29, 2018
• Difference between procfs and sysfs filesystem in Linux November 21, 2018
• How to check open ports in Linux: On local & remote hosts; nc, telnet, nmap, netstat commands. November 21, 2018
• Using for loop in python to test ping response from multiple hosts November 20, 2018
• Sticky Bit, SUID, SGID Bit in Linux. November 18, 2018
• How to change bash prompt color and look in Linux: PS1, PS2, PS3, PS4 Environment Variables. November 18, 2018
• Explanation of Network Bonding and its types in Linux. November 16, 2018
• How to test a port connectivity in Linux on multiple hosts ? November 15, 2018
• Difference between Grub 0.97(Legacy GRUB) and Grub 2 in Linux ? November 15, 2018
• What is NFS hard and soft mount in Linux and which option we should use ? October 29, 2018
• PAM (Pluggable Authentication module) Usage and Configuration in Linux : All about PAM to know. October 6, 2018
• Understanding GPT(GNU Partition Table) and MBR in Linux. October 3, 2018
• How to do system update, patching, its rollback in RHEL or Centos ? October 1, 2018
• Difference between RHEL 5, RHEL 6, and RHEL 7. September 22, 2018
• Difference between NFS v2, v3, v4, v4.1 and v4.2. September 9, 2018
• Explanation of different process states in Linux and how to view or deal with them ? September 8, 2018
• How to scan SCSI disks and storage FC luns in Linux ? August 30, 2018
• Different ways to block a hostname or IP address in Linux ? August 30, 2018
• How to use dig command to debug DNS query in Linux ? August 7, 2018
• How to debug a program using GDB in Linux ? August 6, 2018
• Viewing priority of different running processes in Linux, and how to change it ? August 5, 2018
• Solved: GDB: (no debugging symbols found) error message. August 5, 2018
• Difference between initrd and initramfs: All what you need to know. August 4, 2018
• Unics or Unix, Solaris, FSF and Linux evolution history. August 3, 2018
• How to debug core file using gdb in linux ? August 2, 2018
• How to resolve error message: Undefined command: “debuginfo-install”. Try “help”. while debugging using GDB. August 2, 2018
• What is command grouping in Linux and how to use it ? August 1, 2018
• How to use /dev/tcp and /dev/udp sockets in Linux ? August 1, 2018
• What is /proc/sysrq-trigger in linux and how to use sysrq kernel feature ? July 16, 2018
• How to debug crash dump in Linux using crash and debuginfo ? July 16, 2018
• How to setup kdump in Linux to collect crash dump ? July 16, 2018
• How to enable core dump collection in Linux for every user ? July 15, 2018
• How to solve error: linux/module.h: No such file or directory in C ? July 13, 2018
• How to put multiple files’ output side by side for comparision in Linux ? June 25, 2018
• How to disable crontab “-r” option in Linux ? June 17, 2018
• What are dictionaries in python and how to work with them ? June 12, 2018
• How to create classes and objects in python ? June 12, 2018
• GIT/ GITHUB Cheatsheet with startup commands. June 3, 2018
• Create a command to auto-login to some server. June 3, 2018
• How to install ansible in your Linux or Mac OS system ? May 28, 2018
• How to define and use functions in python ? May 28, 2018
• Which is better raid 10 or raid 01 ? May 15, 2018
• Different parameters available in Linux Bash Shell with examples May 11, 2018
• What data remains in page cache on Linux and how to remove it with one command quickly ? May 10, 2018
• Interesting “else” clause in “for” loop in Python. May 10, 2018
• How to use True, break and continue keywords in python ? May 10, 2018
• How to use “for” loop and “range” function in python ? May 2, 2018
• Why we face Error 17 in Linux during grub boot ? April 30, 2018
• How to take user input(both integer and string) in python ? April 11, 2018
• How to debug python script for beginners ? April 11, 2018
• String and integer comparison in Python April 11, 2018
• How to use strings in Python ? April 6, 2018
• Why we receive IndexError: list index out of range error in python ? April 4, 2018
• Arrays in Python March 26, 2018
• Performing string and integer comparison & printing variables with text in python. March 23, 2018
• Integer calculation in Python March 23, 2018
• How to resolve NameError: name ‘mystring’ is not defined error in python ? March 23, 2018
• Declaring Variables: Integers, float and string in Python. March 23, 2018
• Hello world program in python mentioning interpreter using shebang. March 22, 2018
• Hello world program in python. March 22, 2018
• Verify version of python installed on Linux system March 22, 2018
• How to get a specific line or range of lines’ output from a file in linux ? March 22, 2018
• Comments & if else statement in python March 22, 2018
• How a linux command uses C system call defined in header files? March 17, 2018
• Viewing POSIX system variables in Linux & how to edit them ? March 13, 2018
• How to run any linux command inside AWK command ? March 13, 2018
• How to trace a command or particular system call in the command on Linux ? March 12, 2018
• How to filter lowercase or uppercase words/letters from a file in Linux ? March 12, 2018
• How to list all commands of a package in Linux OR use of info command ? March 12, 2018
• How to find process id of current and sub shell in Linux ? March 12, 2018
• How to create a new folder & cd into the created folder in a single command ? March 12, 2018
• How to add line number in the command output or to a file in Linux ? March 12, 2018
• How to see different PROCESS STATE CODES available in our Linux system ? March 11, 2018
• How to count words in a file without using wc command ? March 11, 2018
• How to perform temporary and permanent kernel parameter tuning in linux ? March 11, 2018
• Default User Home directory in Linux and solaris ? March 11, 2018
• Use of exec command in linux bash shell March 8, 2018
• How to create a custom user command in Linux quickly ? March 8, 2018
• How to get last command argument value in follow up command in Linux ? March 8, 2018
• Difference between nohup and &(ampersand) in linux ? March 1, 2018
• How to debug core file in Linux using gdb and crash utility ? February 27, 2018
• How to setup an alert to know about server crash situation ? February 21, 2018
• How to download youtube Videos & mp3 in Linux ? February 20, 2018
• Brief explanation of process related terms in linux. February 18, 2018
• How to create Zombie process using C code manually ? February 18, 2018
• How to change minimum and maximum UIDs or GIDs assigned by useradd command ? February 17, 2018
• How to generate core file of a process id in Linux ? February 17, 2018