LINUX- show progress bar during dd copy using pv

Warning & Disclaimer: dd is a low level tool. if you are not familiar with it  please do NOT use it. If wrongly used it can wipe off all your data. Always run or play with such commands on TEST Machines first. If you follow this post , you accept you are doing it at your own risk.

Method 1:

dd if=FILE1 of=FILE2
pkill -USER1 dd  

To see output being refreshed continuosly:

watch -n 10 pkill -USR1 dd

Method 2:

pv FILE1 | dd of=FILE2

EXAMPLE: sudo pv /dev/sde3 |dd of= /tmp/mybackup.img

WHERE: /dev/sde3 is the data partition (the input) on my usb drive
AND /tmp/mybackup.img  is the output (the backup)

I have taken this post & modified a bit to make it more clear from Robert’s Blog.



Next3 – Ext3 with snapshots

Storage appliance vendor Ctera has announced that the Next3 filesystem is now available. Next3 is based on Ext3 and adds lightweight snapshots to the former Linux standard filesystem (which has now largely been superseded by Ext4). The data format stored on disk is identical: A Next3 filesystem can also be mounted as Ext3 – although it will be read-only and can’t be written to; existing Ext3 filesystems can be converted to Next3.

Snapshots are stored in special, filesystem-sized sparse files and are created by moving deleted or overwritten data blocks into the sparse file. When accessing the sparse file, all files are available in the version they were in when the snapshot was created – any holes in the snapshot file will automatically be filled in with the unchanged data in the original filesystem. Find more details about Next3 in an article at LWN and a paper released by the developers. Next3 is available under the GPL 2.

The Next3 developers’ target is the integration of their filesystem into the Linux kernel. However, this could prove difficult: Ext4 has already been established as the next development step to follow Ext3, but Next3 develops Ext3 in a different direction which is not compatible with Ext4. Porting the changes in Next3 to Ext4 is quite involved, because Ext4 manages the data on disk via extents rather than block lists.


Technical and commercial comparison of Citrix XenServer and VMware

Citrix XenServer and VMware vSphere are two leading server
virtualization platforms. This document provides a technical and
commercial comparison of XenServer and vSphere, including
installation and maintenance, OS support, high availability,
disaster recovery and other important virtualization concerns that
should be weighed when exploring virtualization solution options.

Get the White Paper here.



VMWare vSphere – Demystifying what is FREE

FREE: VMware vSphere Hypervisor   (Also known as ESXi)

ADV: Free  VMware vSphere Client to administer the server

DISAD: Cannot be managed with vCenter or other management solutions

COMMERCIAL: VMware vSphere

ADV: advanced functionally including centralized management, live migration of virtual machines, automatic load balancing, business continuity, power management, and backup and restore capabilities for virtual machines.

Hence, The extra word “Hypervisor” in the product name is the mystery & decides which one is free & which one must be purchased.

Free can be upgraded by putting a license.


The Tao of UBUNTU

A person with ubuntu is open and available to others, affirming of others, does not feel threatened that others are able and good, for he or she has a proper self-assurance that comes from knowing that he or she belongs in a greater whole and is diminished when others are humiliated or diminished, when others are tortured or oppressed.

~ Archbishop Desmond Tutu, 1999