If Islandora is handling the URLs, you might be able to use Drupal's
redirect module [1].  We use it to support the URLs from our old
website, which we just migrated to Drupal.

But if Islandora/Drupal is not handling the URLs, or if you have
millions, this probably won't work for you.

[1] http://drupal.org/project/redirect

--Andy

On Thu, Aug 30, 2012 at 8:51 AM, Pottinger, Hardy J.
<[log in to unmask]> wrote:
> Hi, we're in the process of migrating an existing digital library to a new
> platform, and we want to ensure that old URLs continue to resolve to the
> items in the new location. The new digital library will be built on
> Islandora, and I am pretty sure we can just map old URLs to new ones
> within Fedora Commons. But, in case we run into trouble, I was wondering