Linux Patch Management

Ravi writes "Any system or network administrator will know the importance of applying patches to the various softwares running on their servers be it the numerous bug fixes or vulnerability checks. Now when you are maintaining just a single machine, this is really a simple affair of downloading the patches and applying them on your machine. But what happens when you are managing multiple servers and hundreds of client machines? How do you keep all these machines under your control up to date with the latest bug fixes? Obviously, it is a waste of time and bandwidth to individually download all the patches and security fixes for each machine. This is where this book named "Linux Patch Management - Keeping Linux systems up to date" authored by Michael Jang gains significance. This book released under the Bruce Perens' open source series aims to address the topic of patch management in detail." Read the rest of Ravi's review Linux Patch Management - Keeping Linux Systems Up To Date author Michael Jang pages 270 publisher Prentice Hall rating 8 reviewer Ravi ISBN 0-13-236675-4 summary This book offers Linux professionals start-to-finish solutions, and examples for every environment, from single computers to enterprise-class networks.

The book is divided into seven detailed chapters, each covering a specific topic related to patch management. In the first chapter, the author starts the narration by giving an introduction to the basic patch concepts, the various distribution specific tools available for the user including Red Hat up2date agent, SUSE YaST online update, Debian apt-get and also community based sources like those in Fedora. What I found interesting was instead of just listing the various avenues that the user has regarding patching his system, the author goes the extra mile to stress the need for maintaining a local patch management server and also the need to support multiple repositories on it.

The second chapter deals exclusively with patch management on Red Hat and Fedora based Linux machines. Here the author walks the readers through creating a local Fedora repository. Maintaining a repository locally is not about just downloading all the packages to a directory on your local machine and hosting that directory on the network. You have to deal with a lot of issues here, like the hardware requirements, the kind of partition arrangement to make, what space to allocate to each partition, whether you need a proxy server and more. In this chapter, the author throws light on all these aspects in the process of creating the repositories. I really liked the section where the author describes in detail the steps needed to configure a Red Hat network proxy server.

The third chapter of this book namely SUSE's Update Systems and rsync mirrors describes in detail how one can manage patches with YaST. What is up2date for Red Hat is YaST for SuSE. And around 34 pages have been exclusively allocated for explaining each and every aspect of updating SuSE Linux using various methods like YaST Online Update and using rsync to configure a YaST patch management mirror for your LAN. But the highlight of this chapter is the explanation of Novell's unique way of managing the life cycle of Linux systems which goes by the name ZENworks Linux Management (ZLM). Even though the author does not go into the details of ZLM, he gives a fair idea about this new topic including accomplishing such basic tasks as installing the ZLM server, configuring the web interface, adding clients ... so on and so forth.

Ask any Debian user what he feels is the most important and useful feature of this OS, then in 90 percent of the cases, you will get the answer that it is Debian's contribution to a superior package management. The fourth chapter takes an in depth look into the working of apt. Usually a Debian user is exposed to just a few of the apt tools. In this chapter though, the author explains all the tools bundled with apt which makes this chapter a ready reference for any person managing Debian based system(s).

If the fourth chapter concentrated on apt for Debian systems, the next chapter explores how the same apt package management utility could be used to maintain Red Hat based Linux distributions.

One of the biggest complaints of users of Red Hat based Linux distributions a few years back was a lack of a robust package management tool in the same league as apt. To address this need, a group of developers created an alternative called YUM. The last two chapters of this book explores how one can use YUM to keep the system upto date as well as hosting ones own YUM repository on the LAN.

Each chapter of the book explores a particular tool to achieve patch management in Linux and the author gives in depth explanation of the usage of the tool. All Linux users irrespective of which Linux distribution they use will find this book very useful to host their own local repositories because the author covers all distribution specific tools in this book. The book is peppered with lots of examples and walk throughs which makes this book an all in one reference on the subject of Linux patch management."

Michael Jang has specialized in networks and operating systems. He has written books on four Linux certifications and one of them on RHCE is very popular among students attempting to get Red Hat certified. He also holds a number of certifications such as RHCE, SAIR Linux Certified Professional, CompTIA Linux+ Professional and MCP.

You can purchase Linux Patch Management - Keeping Linux Systems Up To Date from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

Update: 02/07 14:52 GMT by J : Book rating changed from an intended 4 (of 5) stars to Slashdot-normalized 8 (of 10), by Ravi's request.

Comments

Patches using RPM

[IMightB]

What I want to know is how to issue patches via RPM rather than distributing the whole app again. Wether using some sort of binary diff, or just packaging the changed files. And how to manage things like this with the RPM database. I know that SuSE has got "patch" rpm's but I can't find any info as to how these are created, or how they are viewed/managed by the rpm DB.

Anyone?

Re:Patches using RPM

[jacksonj04]

And yet people like you complain about those who don't keep their PC patched?

You have two choices:

Make things easy for some who can't remember some cryptic command to download source, compile, install, patch, re-patch, re-re-patch, change the config, find it was the wrong config, hunt for the config, change the config, find they have to re-compile, re-compile, re-install, re-re-re-patch and finally use.

Stop whining.

ZENworks Linux Management

[ezs]

This is a nice review of 'patching Linux' - and it's a subject close to my heart. Usual disclaimer - ZLM is partly my product and baby. One thing that the review clearly describes - there's a lot of choice out there. From Red Hat Network; to Novell update; to YaST Online Update - and there there is yum, apt etc etc etc. One of the cool things that ZENworks Linux Management brings to the table is the ability to integrate multiple sources of patches - RHN, YOU, Novell, roll-your-own, apt - and bring them into a central release server and control what goes where. For those that are too small or don't want to shell out for ZENworks - remember there is also the fully open source Open Carpet product - http://opencarpet.org/

Book summary

[MirrororriM]

1. Set up your own package server on the LAN - this means the package server will download from the internet. So you basically have ONE machine downloading from the net - the rest of the machines are done internally.

2. Next, set up your sources.list file to point only to that server.

3. 17 8 * * * root apt-get update; apt-get upgrade

4. ???

5. Profit!!!

Gentoo Linux anyone?

[wolverine1999]

What about Gentoo's system where you use emerge and emerge sync...
Did it get a mention, or not?

Authors Wanted

[Bruce Perens]

We're looking for more authors. All books in the series are placed under the Open Publication License (commercial use permitted, it's a real Open Source license) and made available in source and unencrypted PDF three months after they get to bookstores. Paper copies sell through about as much as other books outside of the series. We get good placement in brick-and-mortar bookstores like Borders and Barnes and Noble. But IMO the biggest benefit to authors is that once sales die down your book won't be locked away while you don't have any rights - a common headache that technical book authors have. Open Source books are living books.

Interested? Write to Mark_Taub at Prenhall.com and say you're interested in being in the Perens series.

Bruce

An alternative approach: Don't patch, use rsync

[bit01]

I like making all files on all machines on a LAN, excluding network addressing, electronic licensing and logs, bit-for-bit identical. Doing so massively reduces management overhead and improves management control.

I've managed networks of several hundred machines this way and it works well. I checksum all files and directories on all machines on a regular basis and if anything's different in time or space I find out why and make sure it doesn't happen again. I've found dozens of very obscure and troublesome software and hardware bugs this way, have very good uptime and I can concentrate on making sure the master machines are well configured rather than waste time trying to put out fires all over the network all the time. If individual machine classes need to have different configurations I partition those differences out and manage them separately

Distributing patch packages is error prone. By working at the file level it's easy to be confident everything is okay. You can also often distribute and back out "patches" (just a list of files to be rsync'ed) in the background very quickly at short notice with minimal impact on users.

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Keep your options open!