System Configurations - Revision history

Martin von Gagern: Undo revision 1628 by Special:Contributions/TkeXwy (User talk:TkeXwy)

2007-07-15T08:56:24Z

Undo revision 1628 by Special:Contributions/TkeXwy (User talk:TkeXwy)

@@ Line 76: / Line 76: @@
 You can then create additinal directories for other machines and check them out to their root directory.
 Let's suppose you are working on a machine called <tt>maschine</tt>. You could do the following:
-  svn mkdir ssh svn://root@macchina/svn/configs/maschine
+  svn mkdir ssh+svn://root@macchina/svn/configs/maschine
-  svn checkout ssh svn://root@macchina/svn/configs/maschine /
+  svn checkout ssh+svn://root@macchina/svn/configs/maschine /
 = Advanced tricks for multiple administrators ''and'' machines =
@@ Line 88: / Line 88: @@
 On every machine where you want to manage the configuration using svn,
-first create the following file named <tt>/usr/local/bin/svn sysadmin</tt>
+first create the following file named <tt>/usr/local/bin/svn+sysadmin</tt>
   #!/bin/bash
   # Taken from http://www.orcaware.com/svn/wiki/System_Configurations
   if <nowiki>[[ -z $SYSADMIN ]]</nowiki>; then
     SYSADMIN=$(
-      read -p "Your (non-root) login name: " NAME </dev/tty >/dev/tty
+      read -p "Your (non-root) login name: " NAME </dev/tty >/dev/tty && \

TkeXwy at 17:03, 14 July 2007

2007-07-14T17:03:08Z

@@ Line 76: / Line 76: @@
 You can then create additinal directories for other machines and check them out to their root directory.
 Let's suppose you are working on a machine called <tt>maschine</tt>. You could do the following:
-  svn mkdir ssh+svn://root@macchina/svn/configs/maschine
+  svn mkdir ssh svn://root@macchina/svn/configs/maschine
-  svn checkout ssh+svn://root@macchina/svn/configs/maschine /
+  svn checkout ssh svn://root@macchina/svn/configs/maschine /
 = Advanced tricks for multiple administrators ''and'' machines =
@@ Line 88: / Line 88: @@
 On every machine where you want to manage the configuration using svn,
-first create the following file named <tt>/usr/local/bin/svn+sysadmin</tt>
+first create the following file named <tt>/usr/local/bin/svn sysadmin</tt>
   #!/bin/bash
   # Taken from http://www.orcaware.com/svn/wiki/System_Configurations
   if <nowiki>[[ -z $SYSADMIN ]]</nowiki>; then
     SYSADMIN=$(
-      read -p "Your (non-root) login name: " NAME </dev/tty >/dev/tty && \
+      read -p "Your (non-root) login name: " NAME </dev/tty >/dev/tty

Martin von Gagern: Typos

2007-06-11T13:18:22Z

Typos

← Older revision		Revision as of 06:18, 11 June 2007
Line 136:		Line 136:
	Now whenever you access the configuration file repository,		Now whenever you access the configuration file repository,
	you will asked your login name unless you set the <tt>SYSADMIN</tt> environment variable.		you will asked your login name unless you set the <tt>SYSADMIN</tt> environment variable.
	~~some~~ commands like checkout make multiple connections,		Some commands like checkout make multiple connections,
	so you'll have to provide your name multiple times.		so you'll have to provide your name multiple times.

Line 152:		Line 152:
	or [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.diff.html svn diff]		or [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.diff.html svn diff]
	to have a look at its previous setting.		to have a look at its previous setting.
	And of ~~yourse~~ you can do [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.revert.html svn revert]		And of course you can do [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.revert.html svn revert]
	to undo changes you have not yet comitted and		to undo changes you have not yet comitted and
	[http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.merge.html svn merge]		[http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.merge.html svn merge]

Lamikae: fixed typo /* Simple case */

2007-01-23T14:33:44Z

fixed typo Simple case

← Older revision		Revision as of 07:33, 23 January 2007
Line 25:		Line 25:
	Now we are ready to commit our configurations to the repository.		Now we are ready to commit our configurations to the repository.
	It is usually a good idea to add and commit files ''before'' you modify them for the first time.		It is usually a good idea to add and commit files ''before'' you modify them for the first time.
	This way you can always compare any revision of the file to its "~~vigin~~" form supplied by your distribution.		This way you can always compare any revision of the file to its "virgin" form supplied by your distribution.
	And always write informative messages so you can later figure out not only what was changed but also why you changed it.		And always write informative messages so you can later figure out not only what was changed but also why you changed it.
	Remember to set <tt>EDITOR</tt> for the root account as well.		Remember to set <tt>EDITOR</tt> for the root account as well if you do not supply the comment from the command line.
	svn commit /		svn commit / -m "vanilla files"

	You may want to have a list of all the files under version control.		You may want to have a list of all the files under version control.

Martin von Gagern: Wrote ideas about sharing (from irc discussion with ruxpin) and completed unfinished paragraph

2007-01-08T13:41:59Z

Wrote ideas about sharing (from irc discussion with ruxpin) and completed unfinished paragraph

@@ Line 54: / Line 54: @@
 Maybe you decide to manage the configuration files for several machines in a single repository.
-So let's create a directory for a single machine in the above repository.
+For the moment I'll consider the machines rather independent from one another,
 Note that we create dir directly in the repository, not in any checked out working copy.
   svn mkdir file:///svn/configs/macchina
@@ Line 61: / Line 67: @@
 instead of checking out the repository root as described above.
 In case you started like described above and only later thought about adding other machines,
-you'll need to move your existing trees to the new location:
+you'll need to move your existing contents to the new location:
   svn move file:///svn/configs/etc file:///svn/configs/macchina/etc
   svn switch file:///svn/configs/macchina /
@@ Line 123: / Line 129: @@
 as I could imagine there would be trouble if you did so.
-Because you changed ownership of the repository, it is probably easiest to
+Because you changed ownership of the repository,
 Now whenever you access the configuration file repository,
@@ Line 147: / Line 156: @@
 [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.merge.html svn merge]
 to undo changes already comitted to the repository.

Martin von Gagern: Initial HowTo based on some personal experience

2007-01-08T12:23:30Z

Initial HowTo based on some personal experience

New page

This page is about '''how to''' manage configuration files (like <tt>/etc/*</tt>) on your machine(s) using subversion.

= Simple case =

Let's start off simple.
I assume you are root, as you are the one modifying the configuration files.
You first create a repository:
svnadmin create /svn/configs

Then you can make your root directory a working copy of this (so far empty) repository:
svn checkout file:///svn/configs /

Now you can start adding things you want to keep under revision control.
When adding directories, make sure to use the <tt>-N</tt> (= <tt>--non-recursive</tt>) flag
to add only the directory itself and not all its contents.
And add directories before any files therein, although you may add both in the same command.
svn add -N /etc /etc/fstab

Now we want to have a look at what we modified so far.
A simple <tt>svn stat</tt> will tell you all the things that are not under revision control so far.
When working with configuration files where you are not interested in many of them this is usually not what you want.
Using the <tt>-q</tt> (= <tt>--quiet</tt>) flag suppresses those unmanaged files.
svn stat -q /

Now we are ready to commit our configurations to the repository.
It is usually a good idea to add and commit files ''before'' you modify them for the first time.
This way you can always compare any revision of the file to its "vigin" form supplied by your distribution.
And always write informative messages so you can later figure out not only what was changed but also why you changed it.
Remember to set <tt>EDITOR</tt> for the root account as well.
svn commit /

You may want to have a list of all the files under version control.
Luckily you can combine the <tt>-q</tt> flag with <tt>-v</tt> (= <tt>--verbose</tt>) to get just that:
svn stat -qv /

The basic work cycle probably is like this:
# if you modify file for the first time:
## add all parent dirs and the file itself
## commit
# edit the file
# check your modification works as expected, otherwise <tt>revert</tt>
# list all modifications
# commit modifications, including message about the reason for this change

= Basic concepts for multiple administrators ''or'' machines =

Maybe you are not the only one administrating the machine.
Assume there are several people who can become root and tweak the config files.
You would then want to know who changed what.
If you are accessing the repository using the <tt>file://</tt> scheme you can simply provide
<tt>--username </tt>''yourName'' to provide this name for the record.
It does not even have to correspond to an existing system account.
svn --username john commit /

Maybe you decide to manage the configuration files for several machines in a single repository.
So let's create a directory for a single machine in the above repository.
Note that we create dir directly in the repository, not in any checked out working copy.
svn mkdir file:///svn/configs/macchina

If you start off like this, you can simply check out the empty directory to the root directory of your machine,
instead of checking out the repository root as described above.
In case you started like described above and only later thought about adding other machines,
you'll need to move your existing trees to the new location:
svn move file:///svn/configs/etc file:///svn/configs/macchina/etc
svn switch file:///svn/configs/macchina /

'''Make sure''' to first move the contents in the repository and only then switch your working copy,
because otherwise you might switch to an empty tree and all your versioned files would be deleted.

You can then create additinal directories for other machines and check them out to their root directory.
Let's suppose you are working on a machine called <tt>maschine</tt>. You could do the following:
svn mkdir ssh+svn://root@macchina/svn/configs/maschine
svn checkout ssh+svn://root@macchina/svn/configs/maschine /

= Advanced tricks for multiple administrators ''and'' machines =

Note that the trick for logging the user by passing <tt>--username</tt>
to each command only works reasonably well with the <tt>file://</tt> scheme.
It won't work with ssh access to another machine.
And it is easy enough to forget to provide your name.
We can solve all this and more by (ab)using the svn facility for defining tunnel applications.

On every machine where you want to manage the configuration using svn,
first create the following file named <tt>/usr/local/bin/svn+sysadmin</tt>
#!/bin/bash
# Taken from http://www.orcaware.com/svn/wiki/System_Configurations
if <nowiki>[[ -z $SYSADMIN ]]</nowiki>; then
SYSADMIN=$(
read -p "Your (non-root) login name: " NAME </dev/tty >/dev/tty && \
echo "$NAME"
)
fi
if <nowiki>[[ -z $SYSADMIN ]]</nowiki>; then
echo "You need to give your name!" >/dev/tty
exit 1
fi
exec /usr/bin/ssh -l sysadmin-svn "$@" --tunnel-user="${SYSADMIN}"

Make it executable:
chmod a+x /usr/local/bin/svn+sysadmin

Register it in the <tt><nowiki>[tunnels]</nowiki></tt> section of your <tt>~/.subversion/config</tt>:
[tunnels]
sysadmin = /usr/local/bin/svn+sysadmin

On the machine where the reporitory is, create a new user named <tt>sysadmin-svn</tt>
and make it owner of the repository:
chown -R sysadmin-svn /svn/configs

To allow access to the repository, it is probably most convenient to create
a ssh public key for root on each machine (using <tt>ssh-keygen</tt>).
I would consider it safe enough to not use a passphrase,
as this key only protects access to the repository and
if someone unauthorized managed to become root you are in trouble anyway.
You can then register all those keys in <tt>~sysadmin-svn/.ssh/authorized_keys</tt>
on the machine with the repository to allow them all access to that account.

Now you can move your machine config to this new scheme:
svn switch --relocate ssh+svn://root@macchina/svn/configs/maschine ssh+sysadmin://macchina/svn/configs/maschine /

'''Take care''' not to combine a <tt>switch --relocate</tt> (to change scheme)
and a simple <tt>switch</tt> (to change repository subtree) into a single step,
as I could imagine there would be trouble if you did so.

Because you changed ownership of the repository, it is probably easiest to

Now whenever you access the configuration file repository,
you will asked your login name unless you set the <tt>SYSADMIN</tt> environment variable.
some commands like checkout make multiple connections,
so you'll have to provide your name multiple times.

= Making use of the information =

So what can you do now your files are under revision control?

Suppose you are looking at some configuration file and want to know why some setting is the way it is.
You'd [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.blame.html svn blame]
the file authors to see who edited it (that's what the user name logging is for)
and in which revision it was last modified.
You can then use [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.log.html svn log]
to have a look at the message of that revision to get a clue why it was modified.
You can use [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.cat.html svn cat]
or [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.diff.html svn diff]
to have a look at its previous setting.
And of yourse you can do [http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.revert.html svn revert]
to undo changes you have not yet comitted and
[http://svnbook.red-bean.com/nightly/en/svn.ref.svn.c.merge.html svn merge]
to undo changes already comitted to the repository.