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Suse Enterprise Administration Bulletin, 2012

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[Dec 10, 2012] SUSE Linux Says Btrfs is Ready to Rock Linux.com

The advanced Butter/Better/B-tree Filesystem, Btrfs, is still labeled as experimental in the Btrfs Wiki and on Oracle's Btrfs page, though the Oracle page looks outdated. Btrfs is an advanced copy-on-write filesystem with a lot of great capabilities: snapshotting and rollbacks, checksumming of data and metadata, RAID, volumes and subvolumes, online defragmentation, compression, and online filesystem check and repair. Snapshots are always interesting to me; they're not backups, but a fast way to restore a system to a previous state. With Btrfs users can manage their own snapshots in their home directories. Btrfs supports filesystems up to 16 EiB in size, and files up to 16 EiB as well. (Which may be almost enough to store all the cute kitten photos on the Internet.)

Most distros include Btrfs, and Btrfs has been included in mainline Linux kernels since the 2.6.29 kernel.  To use it just install the user-space tools. So what's the story, is it ready for prime time or not?

Btrfs is Ready

Matthias Eckermann, senior product manager at SUSE Enterprise Linux, says that Btrfs is ready for production systems, and as of SUSE Linux Enterprise 11 SP2 Btrfs is officially supported, along with Ext3, ReiserFS, XFS and OCFS2 (Oracle cluster filesystem for Linux).

The idea behind supporting multiple filesystems is to enable customers to choose different filesystems for different workloads. The installation default is good old tried-and-true Ext3. In the release notes SUSE recommends XFS for data, and Btrfs for root filesystems.

SUSE is a major Btrfs contributor, and as Mr. Eckermann explains their development strategy is three-fold: First, stability. Then functionality, and then performance. Patches are rigorously tested, and only those that meet SUSE standards are accepted. SLES uses the 3.0.10 kernel, with backports and patches.

SUSE does not support all Btrfs functionality yet. For example, multi-volume handling and RAID, and compression are not yet supported, though they will be.  fsck.btrfs in on the future support roadmap. The scrub command is supported, and you can use it to perform online filesystem check and repair. It runs continually as a background process, and you can also run it manually.

SUSE's nice Btrfs snapshot management tool is called Snapper, and SUSE even provides pre-built Snapper binaries for other distros like CentOS, Debian, Ubuntu, Fedora, and Red Hat.

A notable omission is Ext4; read-only functionality is supported for migrating to a different filesystem. Full read-write support is available with the ext4-writeable KMPkernel module from the SLES11-Extras repository, but it is not supported.

You can migrate from Ext2/3/4 to Btrfs, and you can also migrate back from Btrfs, with one exception: any new data added to Btrfs after conversion will not survive conversion back to Ext2/3/4.

OpenSUSE Has Btrfs

OpenSUSE, the community SUSE edition, gets Btrfs as well, and is more aggressive in pushing out new Btrfs patches. OpenSUSE is free of cost, and SLES has a free 60-day download, so you can test both without spending any money. So is Btrfs ready for production systems? SUSE Linux says yes.

[Sep 20, 2012] Attempt to patch a SLES 10 SP3 returns a curl error 60

See also suse_register aborts with curl error 60 while trying to register against SMT server

For many SP3 systems the prerequisite package for installation of SP4 is RPM to upgrade certificates: openssl-certs-0.8.0-0.10.1. You can download it using the following link:

http://download.novell.com/Download?buildid=_7Pup8oi5zw~

	
# rpm -qi openssl-certs-0.8.0-0.10.1
Name        : openssl-certs                Relocations: (not relocatable)
Version     : 0.8.0                             Vendor: SUSE LINUX Products GmbH, Nuernberg, Germany
Release     : 0.10.1                        Build Date: Wed Aug 31 09:36:18 2011
Install Date: Thu Sep 20 11:13:45 2012      Build Host: bax
Group       : Productivity/Networking/Security   Source RPM: openssl-certs-0.8.0-0.10.1.src.rpm
Size        : 207674                           License: BSD 3-Clause; "MPL 1.1/GPL 2.0/LGPL 2.1 ..."
Signature   : DSA/SHA1, Wed Aug 31 09:36:21 2011, Key ID a84edae89c800aca
Packager    : http://bugs.opensuse.org
URL         : http://www.mozilla.org
Summary     : CA certificates for OpenSSL
Description :
This package contains some CA root certificates for OpenSSL extracted
from MozillaFirefox
Distribution: SUSE Linux Enterprise 10
---Second External mailserver(RTP): /home/bezroun
You need to install it using the command
rpm -Uvh openssl-certs-0.8.0-0.10.1.noarch.rpm

[Sep 20, 2012 ] Updating a SuSE Linux Enterprise 10 SP3 system to SP4 level

This is a pretty capricious update... Use DVD based update instead of YAST.

[Jul 17, 2012]   SUSE now and in the future Hubert Mantel speaks

The beginning of the "return to Nuremberg" period was not so good. Suse 11 SP2 is semi-debugged...
April 12, 2012

The company was set up in Nuremberg by three university students - Hubert Mantel (pic below), Roland Dyroff, and Burchard Steinbild - and a software engineer, Thomas Fehr.

They wanted to build software and provide UNIX support and decided to distribute Linux, offering support.

For those who wonder about the name, Wikipedia says: "The name 'S.u.S.E' was originally a German acronym for 'Software und System-Entwicklung', meaning 'Software and systems development'. However, the full name has never been used and the company has always been known as 'S.u.S.E', shortened to 'SuSE' in October 1998 and more recently 'SUSE'."

In mid-1992, the Soft Landing System (SLS) distribution, the very first GNU/Linux distribution, was produced by Peter MacDonald; Patrick Volkerding then brought out Slackware which was largely based on SLS. And in 1994, the first S.u.S.E Linux emerged, a German version of Slackware.

A couple of years later the company built its own distro, based on the now extinct jurix. The founder of jurix, Florian La Roche joined the company, and was responsible for building YaST, the SUSE installer.

Last year, SUSE, since 2004 a part of Novell, was moved back to Nuremberg as a separate unit after Attachmate Corporation bought Novell and took the company private.

One of the original SUSE hackers, Mantel, rejoined the company a few years back and now has a chance to help the company re-cultivate some of that original culture which made it so well-known.

Over the years, technology companies that lost their original technical leads have tended to go downhill - two cases in point are Sun Microsystems and Microsoft. Mantel's return is thus a big positive for SUSE.

... ... ...

Any commercial GNU/Linux distribution that is successful these days has to sell on its own unique features, not the operating system alone. One of SUSE's unique features is the SUSE Studio. Can you explain how this came about - the thinking behind it and why you feel it has been so successful?

(The) main driving force is probably virtualisation. In the past, you dealt with specific applications, nowadays you juggle with complete virtual machines. This has all sorts of advantages: the systems are separated; you have less security issues, need less hardware for testing, and can simulate complex network setups with just one big machine.

And SUSE Studio lets you create your specific virtual machine(s) easily in some minutes. It's so convenient. I used a Studio created appliance as starting point for my video disk recording system.

How much focus is there on the enterprise desktop these days? Do you think that is a market in which one make money in Europe? Or is it only South American countries - Brazil, for example - which are good markets?

My personal feeling is that the era of the PC (and so of the desktop as well) is slowly coming to an end. People are increasingly using tablets or smartphones for just accessing remote appliances; data is being stored in the cloud. So the desktop is becoming more and more irrelevant. In the long run you probably do not need very much more than an internet browser.

How much has the culture of SUSE changed from what it was when you were there at the start? Are you trying to recreate that mood so that the enthusiasm present at that time - before you were acquired by Novell - returns?

Working in a start-up always differs very much from working in a big company with thousands of employees. Both worlds have their pros and cons. When we were small, we were very agile and flexible; nowadays there is more process and regulation. But I do understand that we need well-defined processes and proper documentation in order to provide our customers the quality level of support and services they need and pay for.

What I really loved about our start-up times was the lack of hierarchy and the incredible efficiency: we all pulled together, everybody knew what he had to do, so we did not need a boss. In fact, it was quite hard to find team leaders when we reached a certain size, because everybody just wanted to continue hacking instead of doing boring paper work and other administrative tasks.

But these were special times (the infamous internet rush end of the nineties) in a special company. Even nowadays, SUSE is a great place to work. I wanted to make my hobby my profession and succeeded. So I'm quite happy :)

Do you still have the chance to get your fingers into code these days? Or have you moved on altogether?

I'm still hacking on code. This is what I always wanted to do since I had my first contact with computers back in 1977. I left the management already in 1999 in favor of being able to work as an engineer. There are better managers than me :)

Twenty years is a long time in the computer industry where 18 months is considered a lifetime. Can you cast your mind back to the way things were when you first started hacking on Linux and how they are now?

It is extremely interesting how things have evolved in the past two decades. The motto of Linus Torvalds and Linux has been: "World domination. Now!" I think Linux has reached this goal albeit in a different way than we initially thought. Computers are ubiquitous, as is Linux. Most people probably do not even know that they are using Linux every day in various ways: The DSL modem is running Linux, the switches, the WLAN access points and even many TV sets. Whenever you access some web server, chances are very high the pages are delivered by a Linux system. And with Android, most smartphones are running Linux as well. With computers and the internet being such an important part of modern life, I think it is very good that big parts of the infrastructure are open and not in control of a single company that tries to lock in customers in order to maximize its profit.

[ Apr 12, 2012 ] SUSE now and in the future Hubert Mantel speaks by Sam Varghese

Apr 12, 2012  | iTWire

ITWIre: SUSE was once the predominant GNU/Linux distribution in Europe. Now that it has relocated back in Nuremberg, how much time do you think it will take before it can regain that status again?

Hubert Mantel: I think the whole computer/Linux world has changed in a way that it no longer makes sense to talk about a predominant distribution in an absolute way. When you talk about mobile devices, the answer certainly is Android; when it comes to desktops in the Linux community, it might be Ubuntu, while many internet and web servers are running some flavor of Debian.

The Linux business has evolved into an industry with many facets where many players have specialised on certain aspects. And in the enterprise segment, SUSE is very well established and plays an important role in providing Linux for global companies.

Given that SUSE originally used a highly customised KDE as its desktop environment, will it go back to this again?

There is no need to "go back to KDE", since we always shipped it :)

One of the things I like most about Linux is that it gives you choice. I have been using at least half a dozen of different desktops in the last years; right now I'm using xfce on my main workstations while my "family machines" continue to run KDE. My wife and children are just users and I think KDE still is the most user friendly interface. The main complaint I have about KDE is that it sometimes starts to be a bit over-engineered; I would prefer it to be less resource hungry.

Any commercial GNU/Linux distribution that is successful these days has to sell on its own unique features, not the operating system alone. One of SUSE's unique features is the SUSE Studio. Can you explain how this came about – the thinking behind it and why you feel it has been so successful?

(The) main driving force is probably virtualisation. In the past, you dealt with specific applications, nowadays you juggle with complete virtual machines. This has all sorts of advantages: the systems are separated; you have less security issues, need less hardware for testing, and can simulate complex network setups with just one big machine.

And SUSE Studio lets you create your specific virtual machine(s) easily in some minutes. It's so convenient. I used a Studio created appliance as starting point for my video disk recording system.

... ... ...

How much has the culture of SUSE changed from what it was when you were there at the start? Are you trying to recreate that mood so that the enthusiasm present at that time - before you were acquired by Novell - returns?

Working in a start-up always differs very much from working in a big company with thousands of employees. Both worlds have their pros and cons. When we were small, we were very agile and flexible; nowadays there is more process and regulation. But I do understand that we need well-defined processes and proper documentation in order to provide our customers the quality level of support and services they need and pay for.

What I really loved about our start-up times was the lack of hierarchy and the incredible efficiency: we all pulled together, everybody knew what he had to do, so we did not need a boss. In fact, it was quite hard to find team leaders when we reached a certain size, because everybody just wanted to continue hacking instead of doing boring paper work and other administrative tasks.

But these were special times (the infamous internet rush end of the nineties) in a special company. Even nowadays, SUSE is a great place to work. I wanted to make my hobby my profession and succeeded. So I'm quite happy :)

Do you still have the chance to get your fingers into code these days? Or have you moved on altogether?

I'm still hacking on code. This is what I always wanted to do since I had my first contact with computers back in 1977. I left the management already in 1999 in favor of being able to work as an engineer. There are better managers than me :)

Twenty years is a long time in the computer industry where 18 months is considered a lifetime. Can you cast your mind back to the way things were when you first started hacking on Linux and how they are now?

It is extremely interesting how things have evolved in the past two decades. The motto of Linus Torvalds and Linux has been: "World domination. Now!" I think Linux has reached this goal albeit in a different way than we initially thought. Computers are ubiquitous, as is Linux. Most people probably do not even know that they are using Linux every day in various ways: The DSL modem is running Linux, the switches, the WLAN access points and even many TV sets. Whenever you access some web server, chances are very high the pages are delivered by a Linux system. And with Android, most smartphones are running Linux as well. With computers and the internet being such an important part of modern life, I think it is very good that big parts of the infrastructure are open and not in control of a single company that tries to lock in customers in order to maximize its profit.

No interview with someone from SUSE is complete without a question about  Microsoft, so here goes. What do you see as the positives from the deal struck with Microsoft in 2006? What are the negatives?

You probably know Gandhi's famous quote: "First they ignore you, then they laugh at you, then they fight you, then you win."

For me, the deal with Microsoft meant that Linux has won. It was the proof that "they" no longer could ignore Linux; it was there and it was to stay. We just had arrived in the computer industry. And we played a role significant enough that a company like Microsoft would see it as advantageous to cooperate with us.

The negatives were mainly on the emotional side. For many Linux enthusiasts, Microsoft just was the "evil empire" and signing a contract with them was perceived as betrayal. But like in real politics, you have to make a compromise once and then if you want to advance.

[Mar 16, 2012] SUSE Linux Enterprise Server 11 SP2 review by Koen Vervloesem

Mar 14, 2012 |  http://www.linuxuser.co.uk/

Such a big jump in kernel version between service packs is not common for enterprise Linux distributions, which are usually quite conservative. For instance, Red Hat Enterprise Linux 5 is still using kernel version 2.6.18, even for its 8th update (RHEL 5.8), released a week after SLES 11 SP2, and in the same way RHEL 6.2 is still using kernel version 2.6.32. Of course these kernel versions contain a lot of backported features from newer kernel versions, but it’s a lot of work to patch these features in and to keep maintaining them.

Instead of backporting and maintaining all those interesting features, SUSE’s engineers have decided to use Linux 3.0 for SLES 11 SP2. This wasn’t done rashly: they did an extensive code review of Linux 3.0 and verified that the kernel’s Application Binary Interface (ABI) is completely compatible with SLE 11′s original 2.6.27 kernel. This guarantees that all software that ran on this kernel can expect exactly the same behaviour from the newer kernel release. So any software that has been certified for SLE 11 is still certified for SLE 11 SP2.

Ext3 is still the distro’s default filesystem, but this is the first time Btrfs (which was introduced as a technology preview in SP1) is officially supported. However, SP2 still uses GRUB Legacy which can’t boot from Btrfs, so when you choose Btrfs in the installer, SLE uses it as your root file system but creates a /boot partition with an Ext3 filesystem.

SUSE has also integrated the Snapper tool that it introduced in openSUSE 12.1 to manage Btrfs snapshots and rollbacks. The basic idea of Snapper is that it automatically creates a snapshot before and after running YaST or Zypper, compares the two snapshots and therefore provides the means to revert the differences between these two snapshots. You can list all the snapshots, see the differences between snapshots and roll them back using a user-friendly YaST module or with the commandline snapper tool. There’s just one caveat: because the boot partition doesn’t use Btrfs, you can’t roll back kernel updates or changes to the boot configuration.

Thanks to Snapper, you can mess up system configuration changes or package installations or updates without having to restore from an old backup and risking to lose some files. Just revert to the snapshot before your problematic change and you’re fine. But Snapper also helps with audits: it’s very easy to discover which changes were made by which YaST or Zypper transaction. Snapper also creates cron jobs for periodic snapshots (which is configurable), so you’ll be able to undo other manual changes too.

SP2 still offers Xen and KVM for virtualization, but it also introduces support for LXC (Linux containers), which is a form of operating system-level virtualization: when you create LXC containers, they are separate virtual servers, but all running on the same underlying Linux kernel of the host system. This lightweight virtualization method has a negligible overhead, as it’s essentially a “chroot on steroids”. On SP2, you can use LXC to isolate various system services from each other.

[Feb 29, 2012]  Release Notes for SUSE Linux Enterprise Server 11 Service Pack 2

Features look very similar to RHEL/Oracle Linux 6.2.  They try to match a pioneering Solaris 10 feature now (Linux Containers).  This feature theoretically permits virtualizing applications without hypervisors VMware or Xen and is much more efficient then hypervisors (to say nothing about very high cost of VMware hypervisor -- all savings from VMware deployment go to VMware :-).  See http://www.ibm.com/developerworks/linux/library/l-lxc-containers/ for details. IMHO B-tree file system (btrfs)  might still be raw. This is an Oracle project to replace outdated Ext filesystem and match efficiency Windows NTFS in Linux. I would stick to Ext4 for 2012 or till Suse 11 SP3.
Note that "syslog-ng  will be replaced with rsyslog" in the future

[Feb 28, 2012] Red Hat vs. Oracle Linux Support 10 Years Is New Standard

The VAR Guy

The support showdown started a couple of weeks ago, when Red Hat extended the life cycle of Red Hat Enterprise Linux (RHEL) versions 5 and 6 from the norm of seven years to a new standard of 10 years. A few days later, Oracle responded by extending Oracle Linux life cycles to 10 years. Side note: It sounds like SUSE, now owned by Attachmate, also offers extended Linux support of up to 10 years.

[Feb 28, 2012] SUSE Breaks With Tradition for SUSE Linux Enterprise 11 SP2

SoMe Information Technology

SLES 11 SP2 comes with a few new tricks besides the new kernel. Customers will get a new version of Samba, for example. Most notable is the supported inclusion of the Btrfs filesystem and tools to manage snapshots. Snapper, a GUI or CLI tool to manage the snapshots, integrates with SUSE’s Zypper and YaST management tools to allow roll back system updates.

The move to the 3.0 kernel probably sounds more drastic than it is. SUSE’s director of product management, Gerald Pfeifer, says that customers "shouldn’t have any problems" with the move to 3.0. "Before doing this, we discussed it with all major hardware vendors and with many of the big software vendors… we didn’t see any problems."

The 3.0 kernel shouldn’t pose problems for most systems that were running SLES 11 SP1, but a handful of applications will encounter some problems. Some applications that literally check for the 2.6 kernel string, however, may fail when moved to a system with the 3.0 kernel. This may include some SAP applications.

For customers that really need to remain on the 2.6 kernel or prior service packs, Pfeifer says that SUSE has support options to keep them on older releases for a longer time. Customers have a transition of about six months to move to the new service pack while retaining support for SLES 11 SP1.

Btrfs Inclusion

The inclusion of Btrfs as a supported filesystem is an interesting choice, but SUSE has historically been a bit outside the box in filesystem choices. SUSE offered ReiserFS as its default for years, though it was never really embraced by the larger community.

Btrfs has not been widely embraced even in community Linux distributions. Fedora has planned to default to Btrfs for several release cycles, but the feature has been repeatedly dropped due to a lack of a filesystem checker (fsck). Pfeifer has suggested that this is not really a necessity.

The features enabled by Btrfs are compelling, though. With Snapper, admins will be able to roll back system changes fairly easily - which means that if Btrfs performance and stability are on par with Ext, it will be a more interesting choice. Pfeifer says that customers will be able to migrate existing systems to Btrfs in place, and revert to the old state if they run into any problems.



Etc

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Bulletin:

Vol 25, No.12 (December, 2013) Rational Fools vs. Efficient Crooks The efficient markets hypothesis : Political Skeptic Bulletin, 2013 : Unemployment Bulletin, 2010 :  Vol 23, No.10 (October, 2011) An observation about corporate security departments : Slightly Skeptical Euromaydan Chronicles, June 2014 : Greenspan legacy bulletin, 2008 : Vol 25, No.10 (October, 2013) Cryptolocker Trojan (Win32/Crilock.A) : Vol 25, No.08 (August, 2013) Cloud providers as intelligence collection hubs : Financial Humor Bulletin, 2010 : Inequality Bulletin, 2009 : Financial Humor Bulletin, 2008 : Copyleft Problems Bulletin, 2004 : Financial Humor Bulletin, 2011 : Energy Bulletin, 2010 : Malware Protection Bulletin, 2010 : Vol 26, No.1 (January, 2013) Object-Oriented Cult : Political Skeptic Bulletin, 2011 : Vol 23, No.11 (November, 2011) Softpanorama classification of sysadmin horror stories : Vol 25, No.05 (May, 2013) Corporate bullshit as a communication method  : Vol 25, No.06 (June, 2013) A Note on the Relationship of Brooks Law and Conway Law

History:

Fifty glorious years (1950-2000): the triumph of the US computer engineering : Donald Knuth : TAoCP and its Influence of Computer Science : Richard Stallman : Linus Torvalds  : Larry Wall  : John K. Ousterhout : CTSS : Multix OS Unix History : Unix shell history : VI editor : History of pipes concept : Solaris : MS DOSProgramming Languages History : PL/1 : Simula 67 : C : History of GCC developmentScripting Languages : Perl history   : OS History : Mail : DNS : SSH : CPU Instruction Sets : SPARC systems 1987-2006 : Norton Commander : Norton Utilities : Norton Ghost : Frontpage history : Malware Defense History : GNU Screen : OSS early history

Classic books:

The Peter Principle : Parkinson Law : 1984 : The Mythical Man-MonthHow to Solve It by George Polya : The Art of Computer Programming : The Elements of Programming Style : The Unix Hater’s Handbook : The Jargon file : The True Believer : Programming Pearls : The Good Soldier Svejk : The Power Elite

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The Last but not Least Technology is dominated by two types of people: those who understand what they do not manage and those who manage what they do not understand ~Archibald Putt. Ph.D


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