Debian: Is it possible/safe to install packages from an older version of the repository?

Question

I'm currently running Debian testing (Wheezy) and am trying to get SCIM working. I want to install the scim-pinyin package, but there is no such package available in the testing repository, although there was one in the previous stable (Squeeze) repository. There is a copy of the package in unstable but not for my architecture (amd64).

Looking at the package versions, I notice that the version in the stable repositories is the same as that in unstable. This being the case, I have two questions:

1. Is there any reason why I can't install a package from an older repository since I would assume that most Squeeze packages will probably have their dependencies met by the package versions currently in testing?

2. What is the best way to achieve this? (Add the Squeeze repository to sources.list? Download the Squeeze package and install it manually?)

Solution 1

In this case, yes, it's possible and safe.

As debian keep dependences tree for each requested package.

At all there is still a risk that some libraries could not exist in two different version together in same installation, due to conflict (port reservation, device driver and so). In this kind of situation, apt would prevent you and ask for what to do. (Come back with another UL question in this case;-)

You could add squeeze.list to source.list.d

(Care! New versions of APT will ignore filename not ending by ".list".):

cat <<eof >/etc/apt/sources.list.d/squeeze.list
deb http://ftp.be.debian.org/debian/ squeeze-updates main contrib
deb-src http://security.debian.org/ squeeze/updates main contrib
eof

add a default directive to /etc/apt/apt.conf.d/

cat <<eof >/etc/apt/apt.conf.d/99squeeze
APT::Default-Release "wheezy";

Than use -t switch to apt-get for overriding default config:

apt-get -t squeeze install scim-pinyin

Solution 2

I did this once -- it was the image viewer gliv, which I wanted because it can do slideshows, but the latest version (in Debian sid) had a bug and terminated on startup. Once "downgraded", it worked.

In /etc/apt/sources.list, say it looks like this:

deb http://ftp.de.debian.org/debian sid main contrib non-free
# deb http://ftp.de.debian.org/debian wheezy main contrib non-free
# deb http://ftp.de.debian.org/debian squeeze main contrib non-free

In that case, I'd uncomment the last two lines, then run sudo aptitude update, then aptitude versions PACKAGE. Spot the version I like, and run sudo aptitude install PACKAGE=VERSION (type the version precisely as in the second column of aptitude's output).

When done, I might want to revert /etc/apt/sources.list so I'm just roaming one Debian release at a time.

Comments

[Admin]

I once installed a package from Lenny on Squeeze. I think it was lib2c.so. Everything worked fine, however I have had, and still have, a bad feeling about it. First i removed the current Squeeze repo, added Lennys (googled for the URL of the archieve servers), installed the nessesary package and moved back to Squeeze repo removing Lennys.

[Admin]

See also bugs.debian.org/cgi-bin/bugreport.cgi?bug=659310 ... it sounds like maybe you shouldn't want to install it.

[Admin]

Check out my answer below; also, this SU question might help you.

[FixMaker]

This makes perfect sense. In the end, thanks to the info in the link posted by @derobert I decided against installing SCIM and used fcitx instead, which is available in wheezy. So I found a solution to my problem but still learnt something new along the way - thanks.

[FixMaker]

I wish I could accept both answers, as both make sense. Thanks for the suggestion.

[Emanuel Berg]

@Lorax: No problem at all, that's a common situation on the SX sites.

[carandraug]

I'd like to point out that files added to sources.list.d are now ignored unless they have the list file extension. So in my case, file would be /etc/apt/sources.list.d/squeeze.list

[Dark Star1]

This answer helped me solve another unrelated library problem. Thanks.

[mozboz]

I tried copying and pasting this into buster so I could use some stretch packages. I found that I did not need the 'updates' - my file stretch.list looked like:deb http://deb.debian.org/debian/ stretch main contrib non-free deb-src http://deb.debian.org/debian stretch main contrib non-free and the default release directive obviously changed to "buster"