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Some of our customers are running Opmantek applications without direct access to the Internet, which can make installations and upgrades quite tedious when new pre-requisites are introduced. We have therefore prepared a document that describes all the common options for working around this problem. The installer also mentions this page if it detects missing pre-requisites but no Internet access.
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It is highly recommended that you let the installer perform the RRD migration on your behalf.
If you have custom models, then it is required to run the RRD migration tool because it also handles the addition of missing RRD entries.
In this situation it will likely complain about your custom RRD types not being known in the new database layout. This is remedied by first comparing models/Common-database.nmis with the one in models-install (admin/diffconfigs.pl will be helpful), then adding your custom entries to models-install/Common-database.nmis and finally rerunning admin/migrate_rrd_locations.pl.
JSON Migration
As outlined in the Release Notes, using the JSON format for (non-RRD) database files is now the default. When you upgrade to version 8.6.0 the installer will offer to perform the migration for you, and it is highly recommended that you let the installer perform the JSON migration on your behalf.
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