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LTS and Release Cycle for Ubuntu

Posted on by admin

LTS is an abbreviation for “Long Term Support”.

We produce a new Ubuntu Desktop and Ubuntu Server release every six months [diagram below]. That means you’ll always have the latest and greatest applications that the open source world has to offer. Ubuntu is designed with security in mind. You get free security updates for at least 18 months on the desktop and server.

A new LTS version is released every 2 years. In previous releases, a Long Term Support (LTS) version had 3 years support on Ubuntu (Desktop) and 5 years on Ubuntu Server. Starting with Ubuntu 12.04 LTS, both versions will receive 5 years support. There is no extra fee for the LTS version; we make our very best work available to everyone on the same free terms. Upgrades to new versions of Ubuntu are and always will be free of charge.

The LTS designation applies only to specific subsets of the Ubuntu archive. The LTS may not apply to all flavors and remixes of Ubuntu. For example, for 8.04 LTS, Kubuntu chose to move to KDE 4.0 and didn’t issue an LTS release. In 10.04, the Netbook Edition was not an LTS. The project will decide which flavors will be LTS and the support duration for each, early in the LTS development cycle.

Some of the latest support windows are illustrated below:

ubuntu-release-cycle-2.png

Release Plan Details

  1. We are more conservative in our package merge with Debian, auto-synching with Debian testing, instead of Debian unstable.
  2. We start stabilizing the release early by significantly limiting the number of new features. We will choose which features we package into the LTS release, versus which ones we leave out and allow for users to optionally download and use from a separate archive.
  3. Avoid structural changes as far as possible, such as changing the default set of applications, lots of library transitions, or system layer changes (example: introducing KMS or hal → DeviceKit would not have been appropriate changes in a LTS).

Furthermore, we define the LTS to be:

  • Enterprise Focused: We are targeting server and multiple desktop installations, where the average user is moderately risk averse.
  • Compatible with New Hardware: We will make point releases throughout the development cycle to provide functional support for new server and desktop hardware.
  • More Tested: We will shorten the development window and extend the Beta cycle to allow for more testing and bug fixing

and clearly state that it is not:

  • A Feature-Based Release: We will focus on hardening functionality of existing features, versus introducing new ones1, except for in the areas of Online Services and Desktop Experience2.
    • 1. Exceptions for priority projects will be documented.~
      ~-2. Because these two areas of development are relatively new, they still require new features to satisfy the original reasons for their creation
  • Cutting Edge: Instead of doing an automatic full package import from Debian unstable, we will do it from Debian testing1. The benefit we gain from not introducing new bugs and/or regressions outweighs the new features and/or fixes we often get from unstable.
    • 1. We reserve the right to selectively pull in updates from unstable, if we believe the stability of the package in Debian is better than what is in the current Ubuntu archive.

 

LTS Schedule

To support our goal of ensuring stability, we plan to make a small number of changes to the release schedule:

  1. Reduced Alpha Stage: Because we will have substantially less new code, we can reduce the number of Alpha releases, and extend the Beta stage to allow for more system testing.
  2. Two Beta Releases: We generally get more bugs filed in the Beta stage because of the increase in user base. In order to address more of these issues, we will provide an additional Beta release.

Quoted from here.

Linux check all ips in a subnet with ping

Posted on by admin

Let’s say you have a subnet 192.168.1.0 / 24 and you want to scan all ip’s to see if any hosts are up:

Type the following command, enter:

 

$ for ip in $(seq 1 254); do ping -c 1 192.168.1.$ip>/dev/null; [ $? -eq 0 ] && echo “192.168.1.$ip UP” || : ; done

Output:

192.168.1.65 UP
192.168.1.66 UP
192.168.1.70 UP
192.168.1.76 UP
192.168.1.253 UP
192.168.1.254 UP

Missing Perl module with phptop how to fix.

Posted on by admin

While trying to run phptop after unzipping it I get the following error:

[root@torino phptop-0.5.3]# ./phptop 
Can't locate Term/Size.pm in @INC (@INC contains: /usr/local/lib/perl5 /usr/local/share/perl5 /usr/lib/perl5/vendor_perl /usr/share/perl5/vendor_perl /usr/lib/perl5 /usr/share/perl5 .) at ./phptop line 24.
BEGIN failed--compilation aborted at ./phptop line 24.
[root@torino phptop-0.5.3]#

 

To fix it I had to follow the coming steps:

[root@torino phptop-0.5.3]# yum install cpan
Loaded plugins: fastestmirror, refresh-packagekit, security
Loading mirror speeds from cached hostfile
 * base: it.centos.contactlab.it
 * epel: mirror.karneval.cz
 * extras: it.centos.contactlab.it
 * updates: mirror.bofh.so
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package perl-CPAN.i686 0:1.9402-127.el6 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
================================================================================
 Package Arch Version Repository Size
================================================================================
Installing:
 perl-CPAN i686 1.9402-127.el6 base 244 k
Transaction Summary
================================================================================
Install 1 Package(s)
Total download size: 244 k
Installed size: 663 k
Is this ok [y/N]: y
Downloading Packages:
perl-CPAN-1.9402-127.el6.i686.rpm | 244 kB 00:00 
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
 Installing : perl-CPAN-1.9402-127.el6.i686 1/1 
 Verifying : perl-CPAN-1.9402-127.el6.i686 1/1
Installed:
 perl-CPAN.i686 0:1.9402-127.el6
Complete!
[root@torino phptop-0.5.3]#

Then run cpan

[root@torino phptop-0.5.3]#cpan

And you will be asked  whether to accept default answers just press <ENTER>/

Lots of test later you are presented with the cpan prompt tyoe install Term::Size as follows:

  • ommit: wrote '/usr/share/perl5/CPAN/Config.pm'
Terminal does not support AddHistory.
cpan shell -- CPAN exploration and modules installation (v1.9402)
Enter 'h' for help.
cpan[1]> install Term::Size

After a long verbose build process assuming all went well ( you need internet connectivity to perform this step) type quit at the prompt as so:

cpan[2]> quit

This returns you to the shell prompt:

[root@torino phptop-0.5.3]# ./phptop 
No phptop records found.
[root@torino phptop-0.5.3]#

Voila !!! the program is working.The error is due to the lack of page reads as yet but the program compiled (JIT) and ran.

 

 

 

VIM cheat sheet

Posted on by admin

< The list of Vim commands >

Working with files
Vim command Action
:e filename Open a new file. You can use the Tab key for automatic file name completion, just like at the shell command prompt.
:w filename Save changes to a file. If you don’t specify a file name, Vim saves as the file name you were editing. For saving the file under a different name, specify the file name.
:q Quit Vim. If you have unsaved changes, Vim refuses to exit.
:q! Exit Vim without saving changes.
:wq Write the file and exit.
: x Almost the same as :wq, write the file and exit if you’ve made changes to the file. If you haven’t made any changes to the file, Vim exits without writing the file.
These Vim commands and keys work both in command mode and visual mode.
Vim command Action
j or Up Arrow Move the cursor up one line.
k or Down Arrow Down one line.
h or Left Arrow Left one character.
l or Right Arrow Right one character.
e To the end of a word.
E To the end of a whitespace-delimited word.
b To the beginning of a word.
B To the beginning of a whitespace-delimited word.
0 To the beginning of a line.
^ To the first non-whitespace character of a line.
$ To the end of a line.
H To the first line of the screen.
M To the middle line of the screen.
L To the the last line of the screen.
:n Jump to line number n. For example, to jump to line 42, you’d type :42
Inserting and overwriting text
Vim command Action
i Insert before cursor.
I Insert to the start of the current line.
a Append after cursor.
A Append to the end of the current line.
o Open a new line below and insert.
O Open a new line above and insert.
C Change the rest of the current line.
r Overwrite one character. After overwriting the single character, go back to command mode.
R Enter insert mode but replace characters rather than inserting.
The ESC key Exit insert/overwrite mode and go back to command mode.
Deleting text
Vim command Action
x Delete characters under the cursor.
X Delete characters before the cursor.
dd or :d Delete the current line.
Entering visual mode
Vim command Action
v Start highlighting characters. Use the normal movement keys and commands to select text for highlighting.
V Start highlighting lines.
The ESC key Exit visual mode and return to command mode.
Editing blocks of text
Note: the Vim commands marked with (V) work in visual mode, when you’ve selected some text. The other commands work in the command mode, when you haven’t selected any text.
Vim command Action
~ Change the case of characters. This works both in visual and command mode. In visual mode, change the case of highlighted characters. In command mode, change the case of the character uder cursor.
> (V) Shift right (indent).
< (V) Shift left (de-indent).
c (V) Change the highlighted text.
y (V) Yank the highlighted text. In Windows terms, “copy the selected text to clipboard.”
d (V) Delete the highlighted text. In Windows terms, “cut the selected text to clipboard.”
yy or :y or Y Yank the current line. You don’t need to highlight it first.
dd or :d Delete the current line. Again, you don’t need to highlight it first.
p Put the text you yanked or deleted. In Windows terms, “paste the contents of the clipboard”. Put characters after the cursor. Put lines below the current line.
P Put characters before the cursor. Put lines above the current line.
Undo and redo
Vim command Action
u Undo the last action.
U Undo all the latest changes that were made to the current line.
Ctrl + r Redo.
Vim command Action
/pattern Search the file for pattern.
n Scan for next search match in the same direction.
N Scan for next search match but opposite direction.
Replace
Vim command Action
:rs/foo/bar/a Substitute foo with bar. r determines the range and a determines the arguments.
The range (r) can be
nothing Work on current line only.
number Work on the line whose number you give.
% The whole file.
Arguments (a) can be
g Replace all occurrences in the line. Without this, Vim replaces only the first occurrences in each line.
i Ignore case for the search pattern.
I Don’t ignore case.
c Confirm each substitution. You can type y to substitute this match, n to skip this match, a to substitute this and all the remaining matches (“Yes to all”), and q to quit substitution.
Examples
:452s/foo/bar/ Replace the first occurrence of the word foo with bar on line number 452.
:s/foo/bar/g Replace every occurrence of the word foo with bar on current line.
:%s/foo/bar/g Replace every occurrence of the word foo with bar in the whole file.
:%s/foo/bar/gi The same as above, but ignore the case of the pattern you want to substitute. This replaces foo, FOO, Foo, and so on.
:%s/foo/bar/gc Confirm every substitution.
:%s/foo/bar/c For each line on the file, replace the first occurrence of foo with bar and confirm every substitution.

Original Post : Here at tuXfiles.org

Virtual Loopback Filesystem: Building A Linux Filesystem From An Ordinary File

Posted on by admin

Unix / Linux has a great inbuilt simplicity to it where you can create file systems on any block set . Now .. a file is a block  set so technically and truly at it’s core a file system can be built on a file and mounted :

I need a 100MB partition for some tests :

Using ofcourse Google as my calculator {pfsssst !!! obviously .. DUH}. I tried 100MB / 512 bytes and got

(100 megabytes) / (512 bytes) = 204 800

 
[root@localhost admin]# dd if=/dev/zero of=disk-image count=204800
204800+0 records in
204800+0 records out
104857600 bytes (105 MB) copied, 41.8633 s, 2.5 MB/s
[root@localhost admin]#

This command leaves me with a 105MB file in which to create my etx3 fs like so :

[root@localhost admin]# ls -al disk-image 
-rw-r--r--. 1 root root 104857600 Jul 13 18:17 disk-image
[root@localhost admin]#

Once this file is created I will use the mkfs to format over the disk-image file:

[root@localhost admin]# /sbin/mkfs -t ext3 -q disk-image
disk-image is not a block special device.
Proceed anyway? (y,n) y
[root@localhost admin]#

Thus a filesystem now resides on my file named disk-image.

We can now use a loopback device to mount the disk-image anywhere we need it:

[root@localhost admin]# mkdir /mnt/test1
[root@localhost admin]# mount
/dev/sda2 on / type ext4 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
tmpfs on /dev/shm type tmpfs (rw,rootcontext="system_u:object_r:tmpfs_t:s0")
/dev/sda1 on /boot type ext4 (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
[root@localhost admin]# mount disk-image /mnt/test1/
mount: /home/admin/disk-image is not a block device (maybe try `-o loop'?)
[root@localhost admin]# mount -o loop disk-image /mnt/test1/
[root@localhost admin]# cd /mnt/test1/
[root@localhost test1]# ls
lost+found
[root@localhost test1]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2              18G  2.7G   14G  16% /
tmpfs                 504M  768K  503M   1% /dev/shm
/dev/sda1             291M   50M  226M  19% /boot
/home/admin/disk-image
                       97M  5.6M   87M   7% /mnt/test1

[root@localhost test1]# touch file1
[root@localhost test1]# mkdir -p top1/bottom1
[root@localhost test1]# tree
.
+-- file1
+-- lost+found
+-- top1
    +-- bottom1

3 directories, 1 file
[root@localhost test1]#

Thus a new file system is now running inside the file.

Backing up that file or moving it to another system would entail now quiescing any applications/scripts working with the file, unmounting the loopback fs system, doing your thing then replace all the cards on the deck 🙂