The Problem On CentOS/RHEL 6, a disk has issue and mdadm command shows /dev/md5 was active, degraded state . # mdadm -Q –detail /dev/md5 /dev/md5: Version : 0.90 Creation Time : Wed Apr 12 09:50:21 2017 Raid Level : raid1 Array Size : 10485696 (10.00 GiB 10.74 GB) Used Dev Size : 10485696 (10.00 GiB […]
Archives for December 2018
LVM VG Metadata Corruption with ‘Checksum error’
The Problem “Checksum errors” are reported when running LVM commands on CentOS/RHEL server. # vgs /dev/mapper/cx0009_lun45: Checksum error /dev/mapper/cx0009_lun48: Checksum error VG #PV #LV #SN Attr VSize VFree vg00 1 7 0 wz–n- 279.12G 159.12G vgcommrmandb 1 6 0 wz–n- 20.00G 44.00M vgcotsoracle 1 1 0 wz–n- 20.00G 4.00M vgcotsorapit 1 1 0 wz–n- 50.00G […]
How to configure xhost to be persistent across reboots in Linux
Introduction The xhost command is the Linux X-Windows server access control program. Depending on the arguments used, xhost grants or denies user/host access (connections) to the local X-server, thereby allowing or denying users/hosts the ability to display X-Windows-based applications e.g. xclock, graphical installers etc. The purpose of this post is to describe how to configure […]
Using cut on Linux Terminal
The cut command The cut command is most often used to select single columns of data from input separated by a single character, such as an /etc/passwd file. For example, the cut command is used to extract specified columns/characters of a piece of text, which is given as follows: -c: Specifies the filtering of characters […]
Supported and Recommended File Systems on Linux
Purpose of this post is to give systems administrators an overview and a comparison of File Systems available on Linux. Linux File Systems One of the most interesting features of the Linux OS is its variety of file systems. File systems can be defined and built on a partition basis. VFAT, ext2, ext3, ext4 and […]
What are the mount options to improve ext4 filesystem performance in Linux
The default mount options are deployed usually for maximum performance while maintaining safety for general usage. There are some mount options to optimize ext4 file system according to the needs of the target usage. barrier=0 This disables the write barriers in Journaling Block Device(JBD). Ext4 file system has barrier=1 by default where ext3 has barrier=0. […]
OpenShift Container Platform : User creation and deletion using htpasswd command
htpasswd is one of the identity providers in openshift. In order to access OCP cluster have to create users, the users can create using htpasswd command, it has many options can use appropriately. -c Create a new file. -n Don’t update file; display results on stdout. -b Use the password from the command line rather […]
How to gzip all or specific files in Linux
The gzip (GNU zip) utility is older and less efficient than bzip2. Its flags and operation are very similar to those of bzip2. A file compressed by gzip is marked with a .gz filename extension. Linux stores manual pages in gzip format to save disk space; likewise, files you download from the Internet are frequently […]