gitolite/doc/1-INSTALL.mkd
Sitaram Chamarty 10289c6d64 warning against server-side fiddling (<sigh>)
I had someone delete the admin repo on the server, then run gl-setup
again, and complain that included config files did not get restored.

There have been others (see below) before with similar demands, but
those at least had the excuse of being provoked by genuine mistakes.
This guy was intentionally breaking stuff server side.

Wish I could say he was stupid, but actually he was probably smarter
than I.  Just that his idea of the limits of gitolite's responsibility
was vastly different from mine.

----

[1] There was this guy who, as root, went on a "chmod go-rwx" spree for
security, which bollixed up gitweb access to all his repos, so he tells
me gitolite should be able to fix all the permissions on the next admin
push at least?  (That is, instead of just setting umask as it currently
does, it should go on a chmod spree just like he did).

[2] Then there was the guy who told me gitolite should re-create all the
"gl-creater" files for his wildcard repos because he was restoring from
a git push --mirror backup and that doesn't preserve those files?  I
tried to tell him that a git push --mirror doesn't preserve "config" or
"description" or "info/exclude" or any of the other files that git (not
gitolite) maintains, but he didn't care -- losing those did not affect
him (or he never had them), but losing these affected access control,
and it's my fault.
2010-10-23 23:01:12 +05:30

14 KiB

gitolite installatation

In this document:


please read this first

important notes

Please make sure you understand the following points first.

  • gitolite runs as a single user on a server, and is invoked via ssh. Thus, every user on the server is a potential "gitolite host".

  • gitolite depends heavily on ssh pubkey (passwordless) access. Do not assume you know all about ssh -- most people don't. If in doubt, use a dedicated userid on both client and server for installation and administration of gitolite.

    To make matters worse, ssh problems in gitolite don't always look like ssh problems. See doc/ssh-troubleshooting.mkd for help.

  • gitolite does NOT like it when people with shell access to the server fiddle with files and directories it controls.

    Apparently this was not obvious to some people.

A gitolite setup has:

  • a server
  • a "hosting user" on the server -- the userid under which gitolite runs. You can have any number of "hosting users" on one server; in fact every user can host their own gitolite instance
  • an "admin user" -- the user who sets up gitolite and configures it
  • the admin user's client or workstation, from which he does all his work

It is possible to have the server and the client be the same machine, and even the admin user be also the hosting user, (i.e., sitaram@server can install and administer a gitolite setup running under sitaram@server, a situation that is common with some hosting services). It's actually fairly easy and safe to do, as long as you have password access to the server for emergency use. However, I will not be documenting it because (a) if you know ssh you'll know how to extrapolate my instructions to do this and (b) if you don't know ssh it'll be a nightmare to support you.

conventions used

Throughout the documentation, we use "sitaram" as the admin user, and his workstation is called "client". The hosting user is "git", and the server is called "server". Please substitute your values as needed.

Also, we often say "the rc file". This means ~/.gitolite.rc on the server. And when we say the "access control rules", or "conf file", or "config file", we mean conf/gitolite.conf on your gitolite-admin clone.

requirements

client/workstation
  • git version 1.6.2 or greater
    • even msysgit on Windows is fine; please don't ask me for help if you're using putty, plink, puttygen, etc., for ssh; I recommend msysgit for Windows and the openssh that comes with it
  • if you're using the "from-client" method of install (see below), the bash shell is needed
    • again, msysgit on Windows is fine

server
  • any Unix system with a posix compatible "sh".
    • people using "csh" or derivatives please don't ask me for help -- tell your admin csh is not posix compatible
  • git version 1.6.2 or greater
    • can be in a non-PATH location if you are unable to install it normally; see the $GIT_PATH variable in the "rc" file
  • perl (but since git requires it anyway, you probably have it)
  • openssh or any ssh that can understand the authorized_keys file format

technical skills
  • if you're installing gitolite, you're a "system admin", like it or not. Ssh is therefore a necessary skill. Please take the time to learn at least enough to get passwordless access working.

  • you also need to be somewhat familiar with git itself. You cannot administer a whole bunch of git repositories if you don't know the basics of git.

  • some familiarity with Unix and shells is probably required

  • regular expressions are a big part of gitolite in many places but familiarity is not necessary to do basic access control.

installation and setup

install methods and deciding which one to use

Gitolite has 4 install methods:

  • package method if you have a gitolite RPM or a DEB available
  • root method if you have root access to the server, and you plan to have multiple "hosting users" on it
  • non-root method if you don't have root access to the server, but you do have at least one account with a password
  • from-client method if you are not comfortable with public keys and server side commands

Here's how you install using these 3 methods. Future upgrades are equally easy -- the steps required for upgrading are marked "(U)".

(package method) directly on the server, using RPM/DEB

  • from your workstation, copy your ~/.ssh/id_rsa.pub file to the server. Put it in /tmp/sitaram.pub.

  • (U) on the server, as root, do the install (urpmi, yum, apt-get, etc.).

  • on the server, "su - git", then as "git" user, run gl-setup /tmp/sitaram.pub.

  • on the client, run cd; git clone git@server:gitolite-admin

(root method) directly on the server, manually, with root access

  • from your workstation, copy your ~/.ssh/id_rsa.pub file to the server. Put it in /tmp/sitaram.pub.

  • (U) on the server, as root, do the following:

    cd $HOME
    git clone git://github.com/sitaramc/gitolite gitolite-source
    cd gitolite-source
    # now checkout whatever branch you want; for early adopters I suggest
    # "pu", as in "git checkout -t origin/pu" for recent gits
    mkdir -p /usr/local/share/gitolite/conf /usr/local/share/gitolite/hooks
    src/gl-system-install /usr/local/bin /usr/local/share/gitolite/conf /usr/local/share/gitolite/hooks
    
  • on the server, "su - git", then as "git" user, run gl-setup /tmp/sitaram.pub.

  • on the client, run cd; git clone git@server:gitolite-admin

(non-root method) directly on the server, manually, without root access

WARNING: if you use this method you'd better know enough about ssh to be able to keep your keys straight, and you'd also better have password access to the server so that if you screw up the keys you can still get on, or be able to "su - git" from some other user on the server.

  • from your workstation, copy your ~/.ssh/id_rsa.pub file to the server. Put it in /tmp/sitaram.pub.

  • if $HOME/bin is not on the default PATH, fiddle with your .bashrc or .bash_profile or similar files and add it somehow.

  • (U) on the server, as "git", do the following:

    cd $HOME
    git clone git://github.com/sitaramc/gitolite gitolite-source
    # now checkout whatever branch you want; for early adopters I suggest
    # "pu", as in "git checkout -t origin/pu" for recent gits
    cd gitolite-source
    mkdir -p $HOME/bin $HOME/share/gitolite/conf $HOME/share/gitolite/hooks
    src/gl-system-install $HOME/bin $HOME/share/gitolite/conf $HOME/share/gitolite/hooks
    
  • on the server, still as "git", run gl-setup /tmp/sitaram.pub.

  • on the client, run cd; git clone git@server:gitolite-admin

(from-client method) install from the client to the server

The advantage of this method is that it forces you to solve the ssh pubkey problem before attempting to install. It works best if you have dedicated userids, one on the server for installing gitolite, and one on the client for administering it.

The disadvantage is that the admin user ends up with two keys -- one for shell access (that he started with) and one for gitolite access (which the script creates if needed).

This in turn forces the admin to use a different URL to access gitolite repos than normal users, which seems to confuse a heck of a lot of people who don't read the prominently displayed messages and/or the documentation.

This method is verbosely documented in this transcript, including outputs of the commands concerned.

URLs for gitolite-managed repos

The URL for normal users (i.e., users other than the admin) is always of the form "git@server:reponame". So, for instance, git clone git@server:testing gets any valid user a copy of the "testing" repo.

In the first 3 install methods, the admin user will also use the same URL format, like git clone git@server:gitolite-admin.

However, in the fourth ("from-client") method, the admin user needs a different URL (gitolite:reponame) to gain access to the gitolite repositories. Check here for why.

special cases -- multiple gitolite servers

package method and root method

With the first two methods of installation, it's trivial to create multiple gitolite instances (say one for each department, on some mega company-wide server). You can even do this without giving shell access to the admins. Here's an example with just two "departments", and their admins Alice and Bob:

  • create userids webbrowser_repos and webserver_repos
  • ask Alice and Bob for their pubkeys; copy them to the respective home directories for convenience
  • run su - webbrowser_repos, then gl-setup alice.pub
  • (similarly with webserver_repos and bob.pub, and so on for others)

That's it. The URL for all web browser projects is now something like webbrowser_repos@server:reponame, and similarly for the others.

Notice that you only have to do this once for each "department", and it's really just one command after creating the userid. None of these admins need to have a command line on the server, so don't give them the passwords if you don't need to -- the pubkey will allow them to be gitolite admins on their domain, and that's quite enough for normal operations.

from-client method

Thanks to Matt Perzel, the easy-install command now takes an optional 4th parameter, which is the "nickname" of the gitolite server. It gets defined in ~/.ssh/config, and if not used it defaults to "gitolite".

So if you used the following command to install gitolite to 2 different servers:

./src/gl-easy-install -q git my.1st.git.server admin_user1 gitolite_server_1
./src/gl-easy-install -q git my.2nd.git.server admin_user1 gitolite_server_2

you will find that ~/gitolite_server_1-admin and ~/gitolite_server_2-admin have been created as respective clones. Or you can re-clone elsewhere:

cd ~/admin1; git clone gitolite_server_1:gitolite-admin.git
cd ~/admin2; git clone gitolite_server_2:gitolite-admin.git

upgrading

Upgrading gitolite is easy. In each method above, just re-do the step that is marked "(U)". Also, if you're using either of the two methods that use the src/gl-system-install command, please make sure you give it the same arguments!

If you've added any new hooks, please also run the next step (gl-setup) also.

Also, remember that some new features may require additional settings in your ~/.gitolite.rc file.

uninstalling

cleaning out a botched install

When people have trouble installing gitolite, they often try to change a bunch of things manually on the server. This usually makes things worse ;-) so here's how to clean the slate.

  • client-side
    • edit ~/.ssh/config and delete the paragraph starting with host gitolite, if present.
    • remove ~/gitolite-admin
  • server-side
    • edit ~/.ssh/authorized_keys and delete all lines between # gitolite start and # gitolite end inclusive.
    • remove ~/.gitolite, ~/.gitolite.rc and ~/repositories/gitolite-admin.git

uninstalling gitolite completely

There's some duplication between this and the previous section, but uninstalling gitolite is described in great detail in doc/uninstall.mkd