CVS update, Piston update, and SVN commit of Drupal core upgrade for deployed site

I am not entirely sure Piston provides a vital role here, but for now I'd just like to say it worked!

Here is the very basic test. Ordinarily you wouldn't be updating core immediately after deploying a new site, but unlike me ordinarily you would be paying attention.

Many of these commands produce lots and lots of output which is skipped here, but some of which will be mentioned below for orientation and knowing what to expect. On a test server:

sudo /srv/scripts/agaric-newproject.sh 6 example example.edu
cd /sites/example/www/
vi CHANGELOG.txt

Shows that Drupal is at 6.3, looking at the most recent (topmost) logged change.

Now (with credit to Using CVS to maintain a Drupal website) we update Drupal core in the central SVN repository that Piston draws from, in a local checkout of this portion at least of the repository structure:

cd /RCS/agaric/drupal-core/drupal-6/
cvs update -r DRUPAL-6-4 -dP
sudo /srv/scripts/svn_add_delete_files

Back to the test server, in /sites/example/www

NOTE: The next line doesn't actually update anything, but experience shows that Piston needs this redundant update or it will fail.

sudo svn update
sudo piston update
sudo svn status -u
sudo svn commit -m "our updated Drupal core"
vi CHANGELOG.txt

Now shows "Drupal 6.4, 2008-08-13" which means success!

The piston update took a very long time, hanging at "Merging local changes back in" for about five minutes. Not a good sign. Here's the full output:

Processing '.'...
Fetching remote repository's latest revision and UUID
Restoring remote repository to known state at r7321
Updating remote repository to r7325
Processing adds/deletes
Merging local changes back in
Removing temporary files / folders
Updating Piston properties
Updated to r7325 (145 changes)

For a bit more about Agaric's use of Piston, see adding a new version of drupal core to Agaric's piston-enabled deployment system.

Apologies for the mane steps specific to Agaric's set-up. We're happy to share all the scripts, and the most exciting part of this documentation is the cvs update -r DRUPAL-6-4 -dP.

Resolution