The Problem When trying to create physical volume , getting the below error error: # pvcreate /dev/mappper/mpath25 Device /dev/mappper/mpath25 not found (or ignored by filtering). The issue can be reproduced at will with the following step: # pvcreate /dev/mappper/mpath25 The Solution Upon checking it was found that start sector was not zeroed out. # pvcreate […]
Archives for February 2021
“Read-only locking type set. Write locks are prohibited. Can’t get lock for [volume group]” – error during lvextend
The Problem Unable to extend LVM filesystem. The following error message is received on running the lvextend command: Read-only locking type set. Write locks are prohibited. Can’t get lock for rootvg resize2fs 1.43-WIP (20-Jun-2013) The filesystem is already 1310720 blocks long. Nothing to do! The Solution The parameter locking_type is set to 4 in /etc/lvm/lvm.conf. […]
“dracut-initqueue[286]: Warning: dracut initqueue timeout – starting timeout scripts” – CentOS/RHEL 7 booting issue
The Problem Messages “dracut-initqueue timeout – starting timeout scripts” are printed loop while booting then an Emergency shell is launched: dracut-initqueue[]: Warning: dracut initqueue timeout – starting timeout scripts dracut-initqueue[]: Warning: dracut initqueue timeout – starting timeout scripts dracut-initqueue[]: Warning: dracut initqueue timeout – starting timeout scripts dracut-initqueue[]: Warning: dracut initqueue timeout – starting timeout […]
“Failed to Start Activation of LVM2 Logical Volumes” and “Unit lvm2-activation-net.service Entered Failed State” – CentOS/RHEL 7 booting issue
The Problem System cannot boot-up properly with below logs: [ OK ] Started File System Check on /dev/xvdd. [ OK ] Started File System Check on /dev/xvdg. [ OK ] Started File System Check on /dev/xvdb. [ OK ] Started File System Check on /dev/xvdc. [ OK ] Started File System Check on /dev/disk/by-label/BOOT. Mounting […]
“WARNING: Failed to connect to lvmetad. Falling back to device scanning” – error while running LVM commands
The Problem The LVM commands showing below errors: # pvs WARNING: Failed to connect to lvmetad. Falling back to device scanning. >>>> Masked Active: inactive (dead) Sep 08 20:34:29 systemd[1]: Cannot add dependency job for unit lvm2-lvmetad.socket, ignoring: Unit is masked. Sep 08 20:34:32 systemd[1]: Cannot add dependency job for unit lvm2-lvmetad.socket, ignoring: Invalid request […]
“error while loading shared libraries: libjli.so: cannot open shared object file: No such file or directory” ‘java -version’ error on Startup
The Problem “java -version” quits with the error message “error while loading shared libraries: libjli.so: cannot open shared object file: No such file or directory” when trying to start the JVM. Case 1 The problem is there if it is run under a normal user or if it is run under the root user $ […]
“java” command does not run the JVM that has been installed
The Problem A JDK/JRE from Oracle has been installed on a Linux machine according to the installation instructions. The “java” command does not run the JVM that has been installed. Java applications can fail to run if an unexpected Java Runtime Environment is found. Example from a Red Hat server: $ java -version java version […]
CentOS/RHEL: “id” command doesn’t list the Group Name against GID for LDAP Users
The Problem While running “id” command against LDAP users, it only displays the gid for some secondary group and the group name is not being printed: # id user1 uid=48254(user1) gid=100(users) groups=100(users),5002(group1),5001(group2),41257(group3),856(group4),56971 And, the below error was logged in /var/log/sssd/sssd_nss.log : (Tue Mar 14 05:40:09 2020) [sssd[nss]] [nss_cmd_getgrgid_search] (0x0010): getgrgid call returned more than one […]
Windows Active Directory Account Shows Inconsistent UID/GID In Different Linux SSSD Clients (CentOS/RHEL)
The Problem The id command shows different UID and GID on different sssd servers for the same Windows Active Directory user. After purging the sssd cache by sss_cache, the UID and GID are still different. 1. Output from one server: # id ad_test_user uid=[UID](ad_test_user) gid=[GID](ad_test_group) groups=[GID](ad_test_group2),[GID](ad_test_group) # sss_cache -u ad_test_user # id ad_test_user uid=[UID](ad_test_user) gid=[GID](ad_test_group) […]
How to install and configure MySQL sys schema
This is general guidance for DBAs who are looking to use the MySQL sys schema. Introduction The MySQL sys schema is a collection of views, stored procedures, and stored functions to help MySQL database administrators get insight into what MySQL is doing and to help use the Performance Schema. However while the sys schema primarily […]