[Mailman-Users] Some detail questions about migrating lists

[Mark Sapiro]

Frank Griffin wrote:
>
>According to the UPGRADE document, file formats have changed as have
>actual files (some new, some gone).  What triggers the 2.1 version to do
>the necessary conversions ?  Is it just finding files of the old version
>and recognizing them as such ?


Yes, as far as the old config.db to new config.pck conversion is
concerned.

As far as other files such as the pending database and qfiles are
concerned, these will be converted by bin/update if you are upgrading
an installation, but if you are simply moving lists from an old to a
new installation, it is best to deal with pending requests and queued
messages on the old system and blow off anything that is left. There
is no automated way of converting these in the new installation.


>Does the last_mailman_version in the
>data directory trigger this ?


No. last_mailman_version tells bin/update whether it needs to do
anything. This comes into play when installing an upgrade, but when
moving an old list's config.(db|pck) into an existing installation, it
is the DATA_FILE_VERSION in the config file itself that triggers the
update.


>There are various minor concerns, such as file permissions, aliases,
>redoing public archive symlinks, and so forth.  This made me wonder if
>it would be easier/possible to run bin/newlist for each existing 2.0
>list in the 2.1.9 system, and *then* bring over the data, lists, and
>archives/private directories.  Advisable ?


No. This is absolutely wrong. If you create the list on the new system
first, Mailman will always see that list's config.pck and will never
look at the config.db that you move over.

My advice is:

Do not create the lists on the new host.

Do not move anything from the data/ directory.

Move only the config.db from the lists/<listname>/ directories.

Move the archives/private/ tree.

Run bin/list_lists which will instantiate every list and convert every
old config.db to a new config.pck.

Run bin/genaliases to create/update aliases.

After conversion, remove the config.db files as if you don't, a
possible future problem in reading the config.pck and config.pck.last
files could cause Mailman to fall back to the then outdated config.db.

Public archive symlinks will be created automatically the first time a
list's configuration is saved. The bin/list_lists accessing and
converting of the config.db files won't do this, but a list post or
accessing the admin web interface for a list will.

-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan