The Problem Messages such as the following are reported when running commands such as partprobe on a CentOS/RHEL system using LVM (Logical Volume Manager) and multipathing e.g. device-mapper-multipath or EMC PowerPath, etc.: Error: Error informing the kernel about modifications to partition /dev/sda1 — Device or resource busy. This means Linux won’t know about any changes […]
CentOS/RHEL 4
How to Change Default Permission of /var/log/messages in CentOS/RHEL
By default, /var/log/messages* are created with read-write permissions for ‘root’ user only. There might be a requirement to make the log files world readable for eg to allow an application to read and process the data in it. Changing the permissions on such files using ‘chmod’ might be a temporary solution as they will be […]
How to Disable “alt+ctrl+Del” Key Combination causing reboot in CentOS/RHEL 4,5
The key combination “Ctrl+Alt+Del”, when pressed on a virtual console (black-screen tty), causes the system to reboot. This is the default behavior and sometimes people don’t like this feature as it may cause accidental reboots of the system. The post provides the procedure on how to disable “alt+ctrl+del” key combination in order to prevent an […]
CentOS / RHEL : How to add new swap partition
Question I have a new disk attached to the system. How can I create a new swap partition using this disk on the system? Solution For the purpose of this post, let’s assume that you do not have any swap configured on your system. /dev/sdc is the drive referenced with no partitions. Since we are […]
CentOS / RHEL 4 : How to configure interface bonding (NIC teaming)
Follow the 4 steps below to configure the bonding interface: 1. configure bonding driver, as well as the bonding mode and parameters using the configuration file /etc/modprobe.conf. # grep bond0 /etc/modprobe.conf alias bond0 bonding options bond0 mode=1 miimon=100 2. configure the save interfaces of the bond using the respective network scripts. # cat /etc/sysconfig/network-scripts/ifcfg-eth1 DEVICE=eth1 […]