Overview
Upgrading NMIS to 8.6.3G 6G is extremely simple: all you need to do is follow the guidance of the interactive installation script, which will perform all the necessary steps that are safely automatable. Since version 8.5.6G the installer also takes care of installing both operating system packages and CPAN perl packages that NMIS depends on.
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For your convenience the installer offers to save a compressed backup snapshot of your NMIS configuration in root's home directory, and a log of the actions that were performed is saved in install.log in the NMIS directory.
Upgrading without any (or limited) Internet Access
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.
RRD Migration
All NMIS Versions since 8.5.6G recommend an updated and simplified directory structure for your RRD files, which is more robust and easier to deal with from an administrative perspective: all of a node's RRD database files are kept within the directory <nmisdir>/database/nodes/<nodename>. (In the past, a node's RRD files were spread across multiple directories; furthermore the directory names did include the node type, which can change under certain circumstances and which can cause all kinds of subtle inconsistencies.)
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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 8.6.3 6 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.
General Upgrade Procedure
Once you've unpacked the NMIS tarball you will see install.pl in the NMIS source directory. Running ./install.pl -h will show you what options it offers.
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