The Linux disk names (e.g. sda1, hdb3, etc.) are not reliable—they may be changed if there are hardware changes, such an adding or removing a disk. Additionally, the order for the Linux device names is not always the same as the order of SATA poets. For example, the disk connected to SATA port 0 (first…
If /etc/fstab file is created with errors or the hardware configuration changes such as adding hard disks, Linux will boot into failure state. We can bypass the fstab failure by adding booting parameters to Linux. We can do this in two methods: Method 1: Boot to single user mode When booting into single user mode,…
This post introduces how to erase / blank / format a DVM+RW media on Linux in the command line. First, you need to find out the device of the DVD/CD+RW drive on your Linux box. For example, on my box with Linux 3.3.4 kernel, my DVD/CD+RW drive is /dev/sr0. You can also see what the…
MPlayer is a universal (nearly) movie/music player on Linux and many more systems. It’s also my favourite player and MPlayer plays movie or music files in any format that I drop to it. Now, let’s take a look at how to use MPlayer play DVD. MPlayer plays “DVD” in many formats: DVD disks, ISO files,…
We introduced how to create a LVM group with two hard disk partitions, which the LVM group can be used for [[setting-up-lvm-backed-xen-domu|installing LVM backed Xen DomUs]]. The LVM volume can have large capacity from several hard disks. However, we may use all the disk space after some time and we may need to extend the…
How to create a LVM group from two hard disk partitions is introduced in this post. Assume we have installed two hard disks /dev/sdb and /dev/sdc to the server, our task now is to create one LVM volume group vg_xen for installing LVM backed Xen DomUs from these two disks. We will do this by…
I have done some I/O performance benchmark test of Xen DomU. For easier management, some of our DomU VMs are using file-backed VBDs. Previously, our VMs are using Loopback-mounted file-backed VBDs. But blktap-based support are recommended by Xen community. Before considering changing from loopback based VBD to blktap based VBD, I have done this performance…
DVD disks are still commonly used in some areas while the disks are not fast and convenient enough for frequent usage. For frequent usage or archiving, an image of the DVD on hard drives will be better. ISO images do not use a particular container format. They are just a sector-by-sector copy of the data…
Colossus is the successor to the Google File System (GFS) as mentioned in the paper on Spanner at OSDI 2012. Colossus is also used by spanner to store its tablets. The information about Colossus is slim compared with GFS which is published in the paper at SOSP 2003. There is still some information about Colossus…