Whenever a new version of Slackware is released, it continues to be updated should a security vulnerability be found or a nasty bug begin to rear its head. For that reason, it's important to keep up with all the patches for your version of Slackware. We call this the -stable branch. There is also a -current branch where frequent and intrusive changes are made, but unless you're willing to work with a broken computer and fix things on your own, we recommend you stick with -stable. Since -stable updates aren't distributed on the disks, you'll need to obtain them from the Internet. Many people and organizations offer mirrors where you can download the entire Slackware tree, or just the patches/ directory in any number of ways. While some mirrors offer web access, the most common ways of obtaining updates are via ftp and rsync servers. The Slackware project maintains a small list of known mirrors organized by country. If you're in doubt as to what mirror to use, simply consult http://www.slackware.com/getslack/ for suggestions. If you know a major university near you, there's a good chance 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 it's best to use a mirror near where you live to achieve the fastest transfer times and use the least amount of Internet resources. So how do you know when there are updates? The best way is to consult the ChangeLog.txt 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, you'll need to check a mirror. darkstar:~# wget -O - \ ftp://slackware.osuosl.org/pub/slackware/slackware-13.0/ChangeLog.txt \ | less 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 *)

While the Slackware team does release strictly bug-fix patches from time-to-time, you're probably most interested in security fixes for vulnerabilities that are discovered in software. The Slackware Project maintains a mailing list that will notify you if any patches are released that treat such serious issues. In order to subscribe to the mailing list, simply send an e-mail to majordomo@slackware.com 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, will mail you an advisory.

Now that we've gone this far, you should feel reasonably competent in your ability to handle 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. Many of these changes are small, but some of them can completely break your system if you haven't prepared for them. 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. The very first thing you should do before attempting an upgrade, is decide if that's really necessary. 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. The second thing you should do is read the CHANGES_AND_HINTS.TXT file on your upgrade disks or a mirror. This file changes between every release, and lists helpful hints and tips to aid you in dealing with the changes. Finally, read the UPGRADE.TXT file as well before proceeding. After doing these things, you may find it easier to backup your configuration files and data, then perform a regular install of the new Slackware release rather than attempt a possibly tricky upgrade. If however, you still wish to continue, make backups of your data and configuration files. At a minimum, it's good practice to backup the /etc and /home directories. This will give you a chance to perform a re-install should anything go wrong with the upgrade. Since every new version of Slackware has a few differences, giving complete instructions here is not only futile, but misleading. Always consult the documentation included on your Slackware disks or your favorite mirror.