7.9. Checking and Adding System Facts

Subscriptions are available to a system based on whether the software is compatible with the system's architecture. For example, there are different products and subscriptions for 32-bit and 64-bit platforms. Red Hat Subscription Manager determines compatibility by collecting a range of facts about the system's hardware and architecture and then comparing it with all available subscriptions.
The collected facts can be viewed, updated to acknowledge a hardware or configuration change, or overridden to force compatibility in the specified areas.
The system facts are very similar to the information in /etc/redhat-release or /etc/sysconfig. In both the Red Hat Subscription Manager GUI and CLI, the facts are represented as simple attribute: value pairs.


Updating the facts resends the information about the system to the Red Hat subscription service so that it can update the list of subscriptions which match the system architecture. Updating the facts is a very good thing to do after hardware upgrades or other important system changes.

7.9.1. Checking Facts from the Red Hat Subscription Manager UI

  1. Launch Subscription Manager. For example:
    [root@server ~]# subscription-manager-gui
  2. Open the System menu, and select the View Facts item.
  3. All of the current facts for the system are listed in the table, broken down into categories. Each category is in a closed list; to reveal all of the facts in that category, click the arrow by the category name.
    To update the facts, click the Update Facts button in the bottom right of the window.

7.9.2. Checking Facts with subscription-manager

To simply list the facts, run the facts command with the --list option.
[root@server1 ~]# subscription-manager facts --list

cpu.architecture: i686
cpu.core(s)_per_socket: 4
cpu.cpu(s): 4
cpu.cpu_family: 6
cpu.cpu_mhz: 2000.010
cpu.cpu_op-mode(s): 32-bit, 64-bit
cpu.cpu_socket(s): 1
cpu.l1d_cache: 32K
cpu.l1i_cache: 32K
cpu.l2_cache: 6144K
cpu.model: 23
cpu.stepping: 6
cpu.thread(s)_per_core: 1
cpu.vendor_id: GenuineIntel
cpu.virtualization: VT-x
distribution.id: Santiago
distribution.name: Red Hat Enterprise Linux Workstation
distribution.version: 6
dmi.baseboard.manufacturer: IBM
dmi.baseboard.product_name: Server Blade
... [snip] ...
To update the facts after a system change, use the --update option with the facts command.
[root@server1 ~]# subscription-manager facts --update

7.9.3. Overriding the Default System Facts

The system facts, as collected after registration, are cached in /var/lib/rhsm/facts/facts.json. The file is formatted in attribute: value pairs, in a comma-separated list.
{"fact1": "value1","fact2": "value2"}
The primary file is generated and maintained by the Subscription Manager service. However, these facts can be expanded by creating additional JSON facts files and dropping them in the /etc/rhsm/facts directory. These JSON files can override existing facts or even add custom facts to be used by the subscription service.

Example 13. Example Facts Override File

vim /etc/rhsm/facts/my-example.facts

{"uname.machine": "x86","kernel_version": "2.6.32","physical_location": "MTV colo rack 5"}