All hardware eventually fails. This is one of the painful side effects of entropy in our universe. For most of the types of hardware used in modern infrastructure, the loss of a single component usually incurs some amount of downtime. Other than the time taken to swap out something like a bad CPU or stick of RAM, sysadmins or users rarely see many long term ill-effects. But unless an admin takes particular care with storage, data loss from disk failures can have immediate and lasting consequences.Continue reading “RAID Types – Explained”
Using lsof to Recover Deleted Files
If an open file is deleted accidentally, it is possible to use lsof to recreate a copy of the file; provided this is done before the file is closed by the application holding it open.
If you have inadvertently removed a file from the filesystem it is still recoverable if the application using the file it still running. This is because the inode is still open and therefore the data blocks are still on the disk until the application closes the file or exits.Continue reading “Using lsof to Recover Deleted Files”
The Linux Filesystem Explained
Have you ever wondered what all the folders on the root (/) directory of the Linux filesystem are for? Which file goes into which directories and why are they saved in those directories? On this post, we’ll check out each folder and what purpose or function they serve for the operating system itself. Continue reading “The Linux Filesystem Explained”
How to effectively use the GREP command
Grep is a very important & powerful Linux commands. It stands for ‘Global Regular Expression Print’ & is used for matching & printing a search pattern or a regular expression from a single or multiple text files. It will look for the pattern if the mentioned files & will than print the result on screen or to an output file.
In this tutorial, we are going to learn to use grep command with examples. Continue reading “How to effectively use the GREP command”
Changing Kernel Parameters on HP-UX
If you are installing an application on HP-UX (usually Database programs) and it requires specific kernel parameters, you can make adjustments using the kctune command. Here’s an example of changing kernel parameters on HP-UX.
HP-UX LVM change VG Max Size
In HP-UX if you need to adjust an existing LVM Volume Group Max Size to accommodate a new physical disk, here is an example which use the vgmodify command.