[support] How to upgrade multisite installations to Drupal 5.0?

[Earnie Boyd]

Quoting Chris Johnson <cxjohnson at gmail.com>:

> Agreed.   Punting support for people who run multiple sites from one install
> with Drupal 5 is pretty bad.  By the time we migrate to D5 sometime this
> summer, I suspect we will have 40 to 80 sites, running from 1 to 3 installs.
>

I would put D5 in a different directory and update sites gradually.  
Add D5 to the DB table prefix and copy the existing data to the D5 
table space before doing the upgrade.  You can point to D4 vs D5 using 
the httpd config files.  This gives you a backout path should you need 
it.  Then when the upgrades are complete you can drop the older tables 
and the D4 version.

Earnie