Author: Minto Joseph

The fsfreeze command, is used to suspend and resume access to a file system. This allows consistent snapshots to be taken of the filesystem. fsfreeze supports Ext3/4, ReiserFS, JFS and XFS. A filesystem can be frozen using following command: #…

strace is a very useful tool which traces system calls and signals for a running process. This helps a lot while debugging application level performance issues and bugs. Aim of this post is to demonstrate the power of strace in…

Multipathing allows to configure multiple paths from servers to storage arrays. It provides I/O failover and load balancing. Linux uses device mapper kernel framework to support multipathing. In this post I will explain the steps taken to troubleshoot a multipath…

There are several tools and technologies available to debug deeper into high CPU utilization in a system; perf, sysrq, oprofile, vmcore, and more. In this post, I will narrate the course of debugging a CPU utilization issue using technologies like perf…

After joining Pythian I was introduced to several configuration management systems and Puppet was one of them. Foreman is a system management tool which can be integrated with Puppet to manage puppet modules and to initiate puppet runs on hosts…

Stat command in Linux can be used to display a file or a file system status. I came across an issue in RHEL4 where a file’s ‘Change time’ is far ahead than the ‘Modification time’ without a change in uid,…