Linux boot sequence includes many stages. Following the BIOS initialisation, the boot loader is being called (GRUB or GRUB-EFI), then GRUB does its magic, and then it loads the kernel and the init RAM FS (initramfs or initrd) to memory. Following that, the kernel is jumped to, and a set of scripts are called from…
You can find bazillion sites explaining Linux LVM, however, I am preparing for my next article, about partition resize for the advanced user, and LVM deep understanding is required, so I have decided to explain some of the internals of LVM for the advanced user. This explains the how it is built more than the…
After major investigations around, I came to the conclusion that a full guide describing the procedure required for online disk resize on Linux (especially – expanding disks). I have created a guide for RHEL5/6/7/8 (works the same for Centos or OEL or ScientificLinux – RHEL-based Linux systems) which takes into account the following four scenarios:…
I am working on an article which will describe the procedures required to extend LUN on Linux storage clients, with and without use of multipath (device-mapper-multipath) and with and without partitioning (I tend to partition storage disks, even when this is not exactly required). Also – it will deal with migration from MBR to GPT…
First, let me state that this is not a desirable action. It can be done, because, as root, there are so many things which are considered “bad practice” you can still do – this is part of what’s ‘root’ is all about – you know what your system needs, and you know how to do…
I have had a system with Oracle ASM diskgroup from which I needed some space. The idea was to release some disk space, reduce the size of existing partitions, add a new partition and use it – all online(!) This is a grocery list of tasks to do, with some explanation integrated into it. Overview…
