Shulou(Shulou.com)06/01 Report--

Today, I will talk to you about whether the server operating system should choose Debian/Ubuntu or CentOS. Many people may not know much about it. In order to make you understand better, the editor has summarized the following content for you. I hope you can get something according to this article.

First of all, I would like to ask all players, you do not feel good about what you have recently played, and then recommend it wantonly. Take some responsibility! He is a server, and sometimes choosing the wrong distribution will kill a group of people!

Yes, now you finally found a version called Ubuntu, so cool, so many packages, casual apt-get, 30, 000 packages lying in the warehouse do not need to compile. That was awesome! Almost all software has a * version! Alas? After two days, you find that Ubuntu is originally from Debian, and Debian is awesome. It's completely community-run, and there are a lot of packages at all. I found Gentoo in two days. Wow, cow! Performance optimization, compilation and recompilation, configure, configure and configure, reduced to * *. After two days, I'm tired of playing Gentoo, isn't it just compiling? There is also Arch ah, this is good, want to compile the compiler, do not want to compile there are default packages. Then the system that has not been updated by pacman for 2 months is all dead after updating.

Your ideology, at any stage, thinks that this stage is the choice. But that's not the case. It's just your interest.

To discuss this issue, you need to know the difference between the two major distributions. RedHat and Debian.

I. version definition

RedHat is a distribution maintained by Red Hat. Its RedHat 9 is a distribution under the name RedHat. After RH9, the version is divided into community-maintained Fedora and enterprise-used EL. And what we call CentOS X is compiled from RHEL X. So in essence, the target user of CentOS is the server of the enterprise.

CentOS has the concept of release, what is the concept of release? When a version is decided, most of its software packages, including Kernel, have already decided on the version. Under this release, there are no special circumstances, and the major version number does not change.

For example, a Kernel version of CentOS 6:

2.6.32-358.el6.x86_64

2.6.32 is the kernel version number, 358 is the packaged version number, and the packaged version indicates the number of times the package has been packaged. It is normal for RHEL to pack a kernel 500,700 times.

For example, some software, 1.1.3 is version, if the definition of the software itself, * one is the bugfix version, the penultimate is the functional version, then you will rarely see functional updates in RHEL! You usually only see bugfix updates! That is, you will only see the update of the small version number.

Debian is a distributed version maintained and contributed by the community, and its optional packages, packages, and actions are all organized by the community.

Debian has no real concept of release. Debian has many warehouses, stable,testing,unstable, experimental. The way Debian organizes the system is that a software first enters experimental, puts it for a period of time, there is bug to repair bug, there is no bug, and after a period of time, it is moved into unstable, so the loop is eventually transferred to stable. So in this case, there is no concept of a stable version in Debian's system. If you use kernel 3.2.1-87 today, I will update it to kernel 3.3.2-5 tomorrow.

-Supplementary content-

I think I have explained my so-called release concept very clearly, but there are still people in the comments telling me that Debian has release. When I say release, I'm not talking about the concept of drawing a timeline and calling a name. It's the concept of version maintenance.

@ Liu Shiwei said that the same is true of Debian. Well, let me prove it to you.

You can get the details of the linux-image-3.2.0-4-amd64 package in wheezy from Debian here and now Debian stable's Linux kernel package is packaged, downloaded, unzipped, and found in

There is a changelog.Debian under the usr/share/doc/linux-image-3.2.0-4-amd64 directory, grep:

Grep wheezy changelog.Debian linux (3.2.57-3) wheezy; urgency=medium linux (3.2.57-2) wheezy; urgency=medium linux (3.2.57-1) wheezy; urgency=medium linux (3.2.54-2) wheezy; urgency=high linux (3.2.54-1) wheezy; urgency=high linux (3.2.53-2) wheezy; urgency=high linux (3.2.53-1) wheezy; urgency=medium linux (3.2.51-1) wheezy; urgency=low linux (3.2.46-1+deb7u1) wheezy-security Urgency=low linux (3.2.46-1) wheezy; urgency=low linux (3.2.41-2+deb7u2) wheezy-security; urgency=high linux (3.2.41-2+deb7u1) wheezy-security; urgency=high

At least in wheezy (stable), he went from 3.2.41 to 3.2.57, at the same time. You can see that each version is packed 1-2 times, 1-2 times! And Debian's unstable walking to stable is really a casual walk.

Linux (3.2.41-2+deb7u1) is the * version of stable, and his previous version was

Linux (3.2.41-2) unstable, OK, 3.2.41 the second time to pack, add one time patch to become stable

Linux (3.2.41-1) unstable, 41 just called once.

Linux (3.2.39-2) unstable, 39 only call twice.

From this process, you can see that, on the whole, Debian is still following Kernel Source. Why? There's nobody here! Relying on piecemeal people to play patch is better than relying on a small version of Kernel itself to update.

Where's RedHat?

Put a Release Note of RHEL 6. 4

Https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/6.4_Technical_Notes/kernel.html

RHEL, which does not follow the small version of kernel source, integrates bugfix itself, mainly security-related patches.

Why not talk to kernel source?

It is mainly the difference between the target users, as I will explain in the next driver. The target user of RHEL is the enterprise's Server, and too many things have been replaced in his Kernel. Disks, network cards, all kinds of drivers. Although Kernel source only takes a small version, it is not very reliable. It's risky to bring it over frequently.

As a matter of fact, after kernel has reached 2.6, there is no real concept of stability. It's just going all the way. Of course, 2.6.32.xx is really based on bugfix. But this quantity is too large, all kinds of trifles, RHEL is not all brought in.

You must argue with me about the version. OK, I won't argue with you. There is a version of Debian Stable. Are you satisfied? In this state of packing twice a kernel, you can use it if you like. Doesn't matter.

But there's only a version of stable,testing that I've never seen before.

To be honest, I really spent a lot of time looking for more information about Debian.

After 11 years of entry into stable, there is indeed a recent update in 08 Apr 2014.

Http://metadata.ftp-master.debian.org/changelogs//main/l/linux-2.6/linux-2.6_2.6.32-48squeeze5_changelog

Lenny, which was released in 2009, is 5.0, and even information is hard to find. If anyone can find lenny, please give it to a kernel changelog.

-the end of the supplement-

And its successor Ubuntu, he has the concept of release, such as 9.04,10.06, etc., when he has identified release, he will not make much version changes in this version.

But the problem is that he learned the shape of CentOS, not the essence of CentOS. Why? Because he wants to pursue the new (two versions a year), and wants to learn from others to eat the server market. This is a completely contradictory thing.

New, easy to do, as long as you follow Debian, there will always be things in the experimental warehouse. Bring it here, test it, repackage it, release it!

Stable? (Ubuntu-Server) it's hard, it takes a lot of manpower, and Debian won't do it for you. Do it yourself? Ubuntu has tried several times, but I have not seen any success so far. Almost always give up hastily.

Second, the power of maintenance

Do you know what it means to maintain a distribution for a server?

CentOS 4.0 2005-03-09

CentOS 4.9 2011-03-02

6 years

Ubuntu 8.04 LTS April 24, 2008

Ubuntu 8.04.4 LTS January 28, 2010

One year and nine months

What about the LTS you said?

Ubuntu 10.04 LTS April 29, 2010

Ubuntu 10.04.4 LTS February 16, 2012

What about the LTS we agreed on?

It is a joke to say that End of the Date is three years old. As long as the next release is published, the number of updates received by the last release is pitiful.

This is the strength of RedHat! As long as you use my distribution, you don't have to worry about it! Where's Ubuntu? I'm kidding, even for LTS, LTS is hardly updated after the new version comes out. Patch? Never seen it before! That is, the real life span of LTS is only 6 months-1 year. How dare you use it? How dare you give it to your company?

One day some software revealed a vulnerability similar to the recent openssl, and users with CentOS 5 got the upgraded rpm the next day. Users with Debian received a large version update and had to update glibc, kernel, and so on packages due to dependencies. Users who use Ubuntu receive an official reply: "apt-get dist-upgrade"

This is the difference in maintenance between these distributions.

When we talk about RHEL, many people do not understand it and think that Ubuntu is "new" and RHEL is "old".

There is a Broadcom network card on your server. CentOS 6 (2.6.32-358.el6.x86_64) users modinfo it.

Filename: / lib/modules/2.6.32-358.6.1.el6.x86_64/kernel/drivers/net/tg3.ko firmware: tigon/tg3_tso5.bin firmware: tigon/tg3_tso.bin firmware: tigon/tg3.bin version: 3.124

Debian testing (3.12-1) users modinfo for a while.

Filename: / lib/modules/3.12-1-amd64/kernel/drivers/net/ethernet/broadcom/tg3.ko firmware: tigon/tg3_tso5.bin firmware: tigon/tg3_tso.bin firmware: tigon/tg3.bin version: 3.133

Do you know which version of the tg3 driver http://kernel.org 's 2.6.32 comes with?

# define DRV_MODULE_VERSION "3.102" # define DRV_MODULE_RELDATE "September 1, 2009"

Is CentOS "old"? Who is driving the driver into the old kernel? Who is testing the compatibility of the new driver with the old kernel? RH! These are all manpower, these are all financial resources.

While ensuring stability and compatibility, RH provides server users with the most complete device matching and driver support as much as possible. And all this! You don't have to worry about stability and compatibility, because RH doesn't update large versions and doesn't bring huge feature updates.

There is another example:

RPS function in google RFS patch in linux kernel Linux 2.6.35.

This is the function that Linux server users dream of, you don't have to worry about multicore CPU being wasted, you don't have to spend a lot of money on expensive multi-irq network cards. But it takes 2.6.35 to have it.

But don't worry, CentOS 6 (2.6.32) has integrated RPS into the 2.6.32 kernel.

Did you see Ubuntu do such a thing? What is Ubuntu up to? I'm busy sending out another version this year.

Why did RHEL do it? Because his user is a server! RPS is such a thing that PC can't be used at all.

I went back to the beginning. I have also made products with Ubuntu, although it is not a server. But the result of the * is not good. I have heard of a colleague's last company using Ubuntu as a server, a thousand-level quantity. After a chat, I found that it was almost as painful as I had predicted.

The basic pain process goes like this.

Encountered a problem-> found that it can only be solved by updating the software version-> this version of the software is no longer available in your current version-> found that you compiled but relied too heavily-> decided dist-upgrade-> found that you needed to span N release-> test dist-upgrade-> 10 machines, 2 succeeded and 8 failed. The phenomenon of failure is different-> painfully solving various problems-> successful dist-upgrade-> discovering that the company's business programs need to be recompiled-> communicating with developers to explain the importance of upgrading-> developers re-debug and test new versions of libraries used in some columns-> deliver new versions.

After reading the above, do you have any further understanding of whether the server operating system should choose Debian/Ubuntu or CentOS? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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