chapter_18.xml

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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
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<chapter>
<title>Keeping Track of Updates</title>

<section>
<title>The -stable Branch</title>

<para>
Whenever a new version of Slackware is released, the Slackware team will,
as needed, release updated packages to fix serious security vulnerabilities
and particularly nasty bugs.  Therefore, it's important to keep up with all
of the patches for your version of Slackware, which is referred to as the
"-stable" branch.  There is also a "-current" branch, which is where we do
our development work toward the next stable release (and as such, there are
often intrusive changes there), but unless you're willing to work with a 
possibly broken system and are able to fix things on your own, we strongly
recommend that you stick with the "-stable" branch.
</para>

<para>
Since -stable updates aren't distributed on the disks, you'll need to obtain 
them from the Internet.  Many people and organizations offer mirrors from 
which you can download the entire Slackware tree (or only the
<filename>patches/</filename> directory) in any number of ways.  While some 
mirrors offer web access, the most common ways of obtaining updates are via 
ftp and/or rsync servers.  The Slackware project maintains a small list 
(organized by country) of known mirrors.  If you're unsure which mirror you
should use, simply consult 
<ulink url="http://www.slackware.com/getslack/">http://www.slackware.com/getslack/</ulink>
for suggestions.  If you have a major university near you, there's a good 
chance that they offer a mirror of numerous open source projects, and
Slackware may be among them.  The only real requirement for a mirror is that 
it be complete, but usually it's best to use a mirror near where you live in 
order to achieve the fastest transfer times and use the least amount of 
Internet resources.
</para>

<para>
So how do you know when there are updates?  The best way is to consult the 
<filename>ChangeLog.txt</filename> on any up-to-date mirror.  You can always 
find the latest changelogs for the "-current" and most recent "-stable" 
branch on the Slackware Project's web page, but if you're running an older 
version of Slackware, you'll need to check a mirror.
</para>

<screen><prompt>darkstar:~# </prompt><userinput>wget -O - \
ftp://slackware.osuosl.org/pub/slackware/slackware-13.0/ChangeLog.txt \
| less</userinput>
Sun Jan 24 20:22:46 UTC 2010
patches/packages/httpd-2.2.14-i486-1_slack12.1.tgz:  Upgraded.
  This fixes a couple of security bugs when using mod_proxy_ftp.
  For more information, see:
    http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3094
    http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2009-3095
  (* Security fix *)</screen>

</section>

<section>
<title>Security Update Mailing List</title>

<para>
While the Slackware team does release updated bugfix-only packages (i.e. 
not security fixes) occasionally, you're probably most interested in 
security fixes for vulnerabilities discovered after the -stable release.
The Slackware Project maintains a mailing list that will notify you of any 
updated packages for such serious issues.  In order to subscribe to the
mailing list, send an e-mail to <email>majordomo@slackware.com</email> 
with the words 'subscribe slackware-security' in the body of the message. 
The majordomo will be happy to add your name to the list, and when new 
packages are released, it will mail an advisory to you.
</para>

</section>

<section>
<title>Upgrading Slackware Versions</title>

<para>
Now that we've gone this far, you should feel reasonably competent in your 
ability to manage your Slackware system.  But what do we do with it when 
there's a new release?  Updating from one release of Slackware to another 
is a lot more complicated than simply updating a few packages.  Each release 
changes a lot of things, and while many of these changes are small, some of
them can completely break your system if you haven't prepared for them and/or
don't understand what is changing and why.  While some Linux distributions 
provide highly automated tools that attempt to handle every tiny detail for 
you, Slackware takes a much more hands-on approach to things.
</para>

<para>
The very first thing you should do before attempting an upgrade is the one
that many people neglect: decide if it's really necessary to upgrade.  If 
the old system is stable and doing everything you want it to do, there may 
be no need to do an operating system upgrade at all.  Assuming you decide
to do the upgrade, then the second thing you should do is read the 
<filename>CHANGES_AND_HINTS.TXT</filename> file on your upgrade discs or 
a mirror.  This file is updated during the development period before every
release, and it lists lots of helpful hints and tips to aid you in dealing 
with the changes.  Finally, read the <filename>UPGRADE.TXT</filename> file 
before proceeding.  After doing these things, you may decide that it's less
trouble and potential for problems to backup your configuration files and 
data and do a fresh installation of the new Slackware release rather than 
attempt a possibly tricky upgrade.  However, if you still wish to continue, 
make backups of your data and configuration files first.  At a minimum, 
it's good practice to backup the <filename>/etc</filename> and <filename>/home</filename>
directories.  This will give you a chance to perform a reinstall if something 
goes wrong with the upgrade.
</para>

<para>
Since every new version of Slackware has a few differences, giving complete 
instructions here is not only futile but potentially misleading.  You should
always consult the documentation included on your Slackware disks or your
favorite mirror.
</para>

</section>

</chapter>