A lot of people get frustrated because they perceive the Debian stable release to be "too old", sometimes because they bought some crazy new hardware gadget which needs a very recent kernel to support, and sometimes just because they've been brainwashed to think that if they aren't running the "newest version" of package foo, then they're somehow inadequate. So they start running unstable (sid).
And then they come into #debian when it breaks.
And then they don't understand why we're so mean to them.
The purpose of this document is to describe what you did wrong, or why you were flamed; and what you should have done differently.
This FAQ is most especially aimed at Slashdot readers. If you aren't sure whether this includes you... it includes you.
Sid users who want to know whether there are any traps awaiting them if they upgrade are advised to check the /topic of the #debian channel, and the Status of Unstable page.
Finally, please note that this document is not intended to be a general Debian FAQ, nor even a #debian channel FAQ. For definitive documentation about Debian, see debian.org. For the #debian (Freenode) channel FAQ, check The Debian wiki.
Sid is the unstable branch of Debian. All of Debian's branches and releases have "code names" which are from the movie Toy Story. For example, Debian 3.0 is code-named "woody". Sid was the kid who broke all the toys. Some people think sid is an acronym for "Still In Development". This is cute, but inaccurate.
What is unstable?Unstable is where packages go after they've been uploaded by the maintainer, and cleared for release by the FTP master. If you use an unstable package, the only thing you can say with any certainty is that it compiled on the developer's system. It may contain horrible bugs.
When packages have met certain criteria, they are automatically moved from unstable to the current "testing" branch. For more information about testing, see the testing announcement.
For more information, see the Debian Releases page.
How do I install sid?The canonical answer is: You don't. You can only upgrade to it from stable or testing. You do that by editing /etc/apt/sources.list and changing your sources from stable to unstable.
There are some unofficial "sid ISO images" out there. They are dangerous, unofficial and obsolete (by definition!). Stay away from them.
It may also be possible to install sid packages instead of testing packages if you're using a net install from the testing branch. This is not supported, but if you want to try it, you're free to do so. It's your machine, after all. Just don't cry if it breaks.
Does sid have package foo?Don't ask us -- you have the same resources available to you that we have! Here are some of them:
If you ask the #debian channel whether sid has something (KDE version 3.2b or GNOME 2.5 or frobbitz version 42), we won't know! We would have to check for you, and then tell you. This is a sign of laziness on your part. You should check for yourself.
Is package foo broken?Once again, how would you expect us to know? If it doesn't work for you, then there's a good chance it's broken -- but your problem may be common among users of package foo, or it may be unique to your system. That's why Debian has a Bug Tracking System. (You'll also see this called the BTS.) Check there before you ask for help with a package in sid. If you don't see your bug there, but you think it's a real problem in the package, then file a bug report yourself. (You can do this with the reportbug package.)
If you don't see your problem listed in the BTS, but you aren't sure whether it's a real bug or just something you did wrong, then by all means ask for help. Be specific when you ask for help -- say what version of Debian you're using, what version of package foo, what you're doing (or trying to do), and what the error message says.
The Status of Unstable page may also contain information relevant to your situation. You should definitely check there before reporting problems.
Failure to do your homework before asking for help with a package in sid demonstrates your laziness. We won't take you seriously until you've shown that you're taking Debian seriously.
How do I know what version of package foo I'm using?If you don't know how to use the Debian package management tools, you should not be using sid! Really. That's probably part of the reason we flamed you.
sgeigerbot has a package management guide that may be helpful for those of you who were smart enough not to use sid yet. For more information, see the man pages (man dpkg, man apt-get, man apt-cache, etc.)
When will package foo version bar be in sid?When it's ready.
But I need package foo version bar right now!Then go ahead and package it yourself. See the information in the Developers' Corner for details.
Can I use sid packages on stable?No. Don't even bother trying. If you do it anyway, you get to keep all the pieces, and we get to laugh at you.
Can I use sid packages on testing?Only if the dependencies are satisfied. In general, sid and testing are usually close to each other, except for when RC (release critical) bugs in some major package like libc or perl cause a slew of things to be held up. So your odds of getting the binary package to work in testing are pretty good... but you still need to check it out yourself.
If the library dependencies aren't satisfied, then you'll need to backport it.
How do I backport a sid package to testing or stable?Install the Debian source (and the development tools, especially debhelper), and then build the package. Step by step:
If that doesn't work, you're on your own.
Aren't there already backports...?Possibly. Check backports.org and apt-get.org first to see if someone has already done it.
Should I use sid on my server?Are you insane? No!
Should I use sid on my desktop?If you think you can handle a broken Debian system, sure. Do you know what to do if libpam0g breaks, preventing all logins? Do you know what to do if grep breaks, causing the boot process to hang forever? These things have happened. They will happen again.
If you'd like to avoid the brown-paper-bag bugs like these, then use testing instead.
Does sid have security updates?Not in the same sense that stable does. If the maintainer of a package fixes a security bug and uploads the package, it'll go into sid by the normal means. If the maintainer doesn't do that, then it won't. The security team only covers stable (and possibly testing... there's a pending issue for that case).
Sid users (hell, all Debian users!) are strongly urged to subscribe to the Debian security announce mailing list. And while you're at it, you should also be on the Debian devel announce list.
When is sid going to be released?Never. Sid will always be the unstable branch. When testing is released, then a new testing will be created (with a new codename), and packages will continue to trickle down from sid into testing just like they do now.