12132017Headline:

RHEL 5 vs RHEL 7 comparision

Command changes for common tasks System basics Task RHEL5 RHEL7 View subscription information /etc/sysconfig/rhn/systemid subscription-manager identity Configure subscription rhn_register subscription-manager rhn_register View system [...]

RHEL 7 – Changed mount behavior at boot – Nofail

Earlier versions of Red Hat Enterprise Linux booted regardless of whether all partitions specified in /etc/fstab could be mounted. This could result in a system appearing “up” and healthy, while booting without required partitions. To [...]

RHEL 7 reset root password

If you lost the root password to the system and you have access to the boot loader, you can reset the password by editing the GRUB2 configuration.  Resetting the Root Password Boot your system and wait until the GRUB2 menu appears. In [...]

RHEL 7 XFS command vs EXT4

Task ext4 XFS Creating a file system mkfs.ext4 mkfs.xfs Mounting a file system mount mount Resizing a file system resize2fs xfs_growfs Repairing a file system e2fsck xfs_repair Changing the label on a file system e2label xfs_admin [...]

How can I collect system information to provide to Red Hat Support for analysis when the system hangs?

Note: This document only covers common situations with unresponsive systems. Please consult Red Hat Support for specific cases: Red Hat Technical Support – contact numbers and availability For root cause analysis of why a system became unresponsive, [...]

How to generate a Java thread dump on Linux/Unix?

We always need to Java Therad dump to troubleshoot application server issues. You can use the following command to generate Java thread dump. kill -QUIT or kill -3 You can find more info the following link. https://access.redhat.com/site/solutions/18178