"Failed to Get Path Uid" - Multipathd Error Message With Non-Multipathed Devices
The Problem At the time starting multipathd, error messages like below are logged onto /var/log/messages with …
Linux
CentOS/RHEL: Removing and Adding New Disk, Not Showing Correct Size (EMC Storage)
The Problem Two LUNs of 20 GB were removed and new LUNs of 240GB presented to the server. EMC storage is used.
/Usr/Bin/Chcon: Failed to Create Security Context: : Invalid Argument
The Problem During boot, a message related to SELinux appeared in the console log as shown below: /usr/bin/chcon: failed …
How Cron.allow and Cron.deny Can Be Used to Limit Access to Crontab for a Particular User
In most Linux distributions, access to crontab can be control by accessing two files /etc/cron.d/cron.deny and …
How to Disable High-Resolution Timer in CentOS/RHEL 6
This post introduces how to disable high-resolution timer configured in Linux kernel internally. To disable …
Permission Denied to New User Created While Doing Ssh
The Problem Getting permission denied when we are trying to do ssh to the system using new user created $ ssh user1@[ip …
How to Stop Brute Force Ssh Attempts in CentOS/RHEL Using Sshd_config, TCP Wrappers and Iptables
You may have seen a large number of login trials in your Linux box, similar to below: Jan 25 01:37:27 [_HOST_] …
Understanding Shell Parse Order
Shell Parse Order Parsing controls how a shell processes a command line before it executes a command. A shell has a …
Understanding User Startup Scripts - /Etc/Profile, $HOME/.Profile, $HOME/.Kshrc
User Startup Scripts When a user logs in using sh or ksh, configuration scripts run in the following order: /etc/profile …
How to Integrate CentOS/RHEL 8 Server With Microsoft Active Directory Using Adcli
This post describes how to use adcli to integrate a CentOS/RHEL 8 server into Microsoft Active Directory. 1. Install …
How to Copy Files and Directories to and From Another System With 'Rcp' Command
Copying Files or Directories To and From Another System You can use the rcp command to copy files or directories from one …