Showing posts from July, 2016

Lesson Learned On Logical Volume Management and RAID

The lesson is this; that just because you can doesn't mean you should.

I wiped off my RAID array and the data in it. It has around 300+G there, mostly downloaded, recoverable, and back-up'd to a CD/DVD content. I was trying to employ Logical Volume Management or LVM on an existing RAID array. After tackling RAID these couple of months, I figured I'm ready to face another monster. LVM is awesome because it can do partitioning, resizing, formatting, creating snapshots, while the system is online. You do not have to take it offline which to me is like magic.

Now that the data is gone, there really is no reason not to LVM the RAID. So after reinstalling my operating system (which is another long story), I reassemble RAID with:

#mdadm --assemble /dev/md0  /dev/sda  /dev/sdb  /dev/sdc

and checked the status of the array with:

#cat /proc/mdstat
#mdadm --detail /dev/md0

I checked the status of all the logical volumes with any of the following commands:

#pvdisplay     ;to check …


July 2016 - San Mateo, Philippines --
Donato Roque @ubuntu-16.04 mobile: 63-918-572-1710 I'm on twitter,facebook, and this is my blog. Consider using my pgp keys for privacy.

RAID: Added 1 x 2TB Hard drive

I talked about RAID in my system before here and here. My present set up is: /dev/sda5      SSD      223GB   EXT4    /   /dev/sdb1     HHD      2TB       Linux raid      /media/user /dev/sdc1      HHD      1TB       Linux raid     /media/user
New:     /dev/sdd1      HHD      2TB      unpartitioned - free space
RAID: /dev/md0        2 devices    /dev/sdb1   /dev/sdc1

/dev/sdc1 is old. It has 27,500 hours of use according to smartctl. You can open the terminal and type:
#smartctl -a /dev/sdc
to get collected data from the device. Among other attributes see Power-on-hours to get the total hours this hard drive has been spinning. Also pay attention to 5 Attribute the allocated Sector Count. Any value you see other than 100 there, you should move your data somewhere else. 
I have a RAID5 which includes this device. So any warning notification I can fail and remove it. Replace it with a new hard drive. I am completing my RAID 5 array with a new hard drive today.
After installing the hard drive to your …

GNOME-terminal Rocks

Using Ubuntu 16.04 I was wondering if "avconv" is already installed. I am in fact curious if a bunch of packages are installed. I open GNOME-Terminal with Cntrl+Alt+T and type the name of the package. I get info and suggestions on how to install it. In the case of "avconv" it is called by another name. 
That's service and quite helpful.
Donato Roque @ubuntu-16.04 mobile: 63-9185721710 I'm on twitter,facebook, and this is my blog. Consider using my pgp keys for privacy.

Unpatched Software Is A Security Issue

Ubuntu Linux forum was hacked last July 14th. Canonical the company developing Ubuntu disclosed that the forum's database was hacked and data was compromised including hashed passwords of 2 Million users. The hackers used a known vulnerability in an unpatched software the forum is using in its servers. 
In the Linux world, the number one security isssue is updating the operating system and the software that we use with it. The first ones to violate this are the servers. Servers simply run old vulnerable software. 

Donato Roque @ubuntu-16.04 mobile: 63-9185721710 I'm on twitter,facebook, and this is my blog. Consider using my pgp keys for privacy.

GUI in Thunderbird Problem

After downloading Skype for linux yesterday and installing it, my desktop applications are fine. Today I opened Thunderbird and the GUI is back to a 90's theme. I downloaded evolution mail and configured my email accounts in minutes. 
In Linux, there's more than one way to skin a prey.

Resized The RAID And the Data Is Safe

The <a href="">last post,</a> I was talking about resizing a component of my existing RAID. I was worried about losing data.

Here's how I did it without data loss.

/dev/md0                   /dev/sdb1        2TB
                                  /dev/sdc1        1TB

I am increasing the size of the partition and it's an important distinction because the order of the steps would be different otherwise. Check the status of the RAID array with:

$cat /proc/mdstat

Put a fail flag on the partition and remove it.
$sudo mdadm /dev/md0 -fail /dev/sdb1 --remove /dev/sdb1

Then we have to use fdisk to handle the physical resizing of the device. fdisk is an interactive application in text mode. So-
$sudo fdisk /dev/sdb1
-h     for help
-p     for primary partition
-d     delete
-n     new partition
if uns…

Resized RAID Array

RAID is Redundant Array of Independent Disks. It is a technology in virtualization which allows several devices to be grouped together and used as if there is only one device. If I have two or more hard drives I can group them together in a RAID and my computer will treat it as one device. RAID's purpose is for data redundancy and performance. I use software RAID in Linux. The other kind is hardware RAID in which you depend on chipsets to manage the RAID.

I have a RAID5 array consisting of 1x1TB and 1x2TB. I bought a new 2TB hard drive and I want to add it to the RAID.   To make matters complicated I only made a 1TB partition out of the 2TB hard drive when I created the original RAID. I want to use the entire 2TB capacity of the hard drive and then add the newly bought 2TB hard drive to the RAID.

I have been using the RAID array since April 2016, so there's data written on this array now.

old RAID arr…

I'm Back In Ubuntu

Hi Reese

I reinstalled ubuntu 16.04 yesterday. I was able to use the live usb I have of Xenial. So that bit of paranoia saved my skin. I used the whole SSD and told the installer to just wipe the old one off. I have 16 GB of swap. I have /boot. I have full disk encryption including the swap partition.

I also ticked the option to encrypt my /home. It gave me a key. So as I understand this, if I can't log into my desktop ubuntu anymore I will need the key to decrypt the /home and get access to my data.

The installer downloaded all the necessary codecs for the music and video, including flash. Nice of the installer to include that option. It was quick less than 40 minutes and I have ubuntu 16.04 in my hard drive. Bringing all the packages up to date is another story. I guess if you have a very fast connection it won't take you as long as I have.

I have to get my back ups from two sources. First I have a USB backup. Sec…