In Fedora 3, a URL is provided to Fedora for the location of the external datastream. For example, the following URL is common in our use case, and prepared by us in advance when building the "ingest FOXML" originally presented to Fedora:
Fedora 3 modifies this URL (if memory serves) on ingest if the domain matches the fedoraServerHost parameter in fedora.fcfg.
<param name="fedoraServerHost" value="collections.nlm.nih.gov">
The URL is then modified in the stored FOXML to be:
On access, Fedora 3 then modifies (I believe) this stored URL so that it is again resolvable, according to fedoraServerHost in fedora.fcfg.
The migration tool migrates this stored URL as the following URL, which is no longer resolvable:
This request is to provide a configuration parameter in the migration tool to allow such URLs to mapped during migration so that they are resolvable again. Something like fedoraServerHost:collections.nlm.nih.gov.
Although it may be possible to infer this value from fedora.fcfg on the host machine, it seems better to allow this to be an option on execution of the migration tool on the command line, as our fedoraServerHost values in fedora.fcfg have changed over time.