Migrating a Disconnected System

Some systems may never be connected to an external network or may be prevented from accessing CentOS Network or a Satellite system. These systems still require valid subscriptions and product certificates, though.

The rhn-migrate-classic-to-rhsm uses the information in /etc/sysconfig/rhn/systemid to get the previous registration information and map channels to certificates. If a system is disconnected, it may not have a systemid file.

Most systems, even ones never registered with RHN Classic, do have an installation number. When CentOS software is purchased through a vendor, the purchased software is identified in an installation number or subscription number (described in ) in the /etc/sysconfig/rhn/install-num file.

The installation number is in essence a code which contains all of the information about the products and versions purchased for the system. For example, this installation number shows that it is valid for RHEL Client and RHEL Workstation channels. 

[root@server ~]# python /usr/lib/python2.4/site-packages/instnum.py da3122afdb7edd23
Product: RHEL Client
Type: Installer Only
Options: Eval FullProd Workstation
Allowed CPU Sockets: Unlimited
Allowed Virtual Instances: Unlimited
Package Repositories: Client Workstation
key: 14299426 "da3122"
checksum: 175 "af"
options: 4416 "Eval FullProd Workstation"
socklimit: -1 "Unlimited"
virtlimit: -1 "Unlimited"
type: 2 "Installer Only"
product: 1 "client"
{"Workstation": "Workstation", "Base": "Client"}

For a system which is not connected to either RHN Classic or a Satellite system, the installation number can be used to transition the product information from the older channel-based subscription model to the X.509 certificate model, managed by Subscription Manager.

The install-num-migrate-to-rhsm script identifies the channels that a disconnected system is subscribed to and then copies in the appropriate product certificates. Simply run the command: 

[root@server ~]# install-num-migrate-to-rhsm

The script copies in the product certificates for the channels into the /etc/pki/product directory.

Once the system is migrated, it can be registered remotely and have entitlement certificates installed as described in .

Even though the system is not registered, the system facts display what script was used for migration. 

[root@server ~]# subscription-manager facts --list | grep migr
migration.migrated_from: install_number

Because the system was not previously registered with RHN Classic, the migration facts do not include a system ID number.