[Mailman-Users] Backing up Mailman list installations

Barry A. Warsaw barry at zope.com
Thu Nov 29 17:14:03 CET 2001

>>>>> "GW" == Greg Ward <gward at mems-exchange.org> writes:

    GW> Mailman ".db" files, despite the name, are *not* Berkeley DB
    GW> files.  They are Python marshall files.  (In Mailman 2.1, they
    GW> will be called ".pck" and become Python pickle files.)

    GW> In any event, I'm pretty sure they are platform independent.

Correct.  They are platform independent.

Note that Python marshals are not guaranteed to be compatible across
Python releases, although in practice I don't think we've ever broken
this, at least for the data types that Mailman stores.  However, this
was one of the factors for moving to Python pickles in Mailman 2.1,
which /are/ guaranteed to be compatible across Python versions,
platforms, endian-ness, etc. etc.

You may still want human readable versions of the database files
though, for other reasons.  It's not a priority of mine to provide
that, but it wouldn't be hard to write, e.g. a pickle <-> XML
conversion tool.  Contributions are welcome <wink>.


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