In Linux, .rpmnew and .rpmsave files are created by the RPM Package Manager during the installation or upgrade of software packages. These files are part of RPM’s mechanism […]
How to install latest python with openssl on CentOS/RedHat/Oracle Linux 7
The tutorial used here is done on Oracle Linux 7. Download and extract the latest python Install the pre-requirements As latest python is not compatible with the default […]
How to rewrite sender address in postfix using canonical_maps
To rewrite sender addresses in postfix using canonical_maps, you need to configure postfix to use a canonical map file. Create the canonical map file: First, create a file […]
What does “mounted filesystem with ordered data mode. Opts: (null)” means?
The message “mounted filesystem with ordered data mode. Opts: (null)” is typically a kernel log or system message related to the mounting of a filesystem on a Linux […]
IP Address Classes
IP address classes were a part of the original addressing scheme defined in the Internet Protocol (IPv4). However, the concept of classes is largely obsolete due to the […]
Chrony vs NTP
Chrony and NTP (Network Time Protocol) are both protocols and software implementations designed to synchronize the clocks of computers on a network. They aim to ensure that the […]
Why Kdump generates incomplete vmcore?
Kdump is a kernel crash dumping mechanism in Linux that allows you to capture a memory dump (vmcore) when the kernel encounters a critical error or crashes. The […]
growpart fails with “NOCHANGE: partition 2 is size 61888512. it cannot be grown”
Trying to extend partition fails with following error: Check the partion You can see /dev/vda consists of 3 partitions. You can extend only the last partition (/dev/vda3 here). […]
auditd service fails to start with error “Could not open dir /var/log/audit (No such file or directory)”
Starting auditd service fails: The var/log/messages shows: Here, the /var/log/audit is missing. Resolution: