How to calculate the number of subscriptions needed ?
Subscriptions are valid for 2 sockets (physical) or 2 VMs (virtual).
To determine how many subscriptions you need for physical hardware, add up the total number of sockets in the hardware that will run RHEL and divide by 2. If, for example, you have 4 servers with two sockets and 2 servers with 1 socket, that's a total of 10 sockets. Therefore, you need 5 subscriptions.
To determine how many subscriptions you need for virtual machines, add up the total number of VMs and divide by 2. If, for example, you have 100 VMs, you need 50 subscriptions.
How to choose between 1 and 3 years ?
Buying RH00003, RH00004 and RH00005 subscriptions for 3 years instead of 1 provides you with a 10% volume discount.
Also, buying a 3-year subscription instead of a 1-year subscription has the advantage of cutting the paperwork burden of two renewals and diminishes the risk of losing support and maintenance coverage due to a forgotten or late renewal.
Is my RHEL subscription valid for any version of RHEL ?
RHEL subscriptions are valid for any version of RHEL (5, 6, 7 and 8), provided the OS is not End Of Life. Please go to https://access.redhat.com/support/policy/updates/errata to view detailed information about Red Hat Enterprise Linux Life Cycle.
Migrating a RHEL server from one version to another has no impact on the subscriptions.
Which support level should I choose ?
Standard support is the standard level support that you should choose by default if you do not have any particular needs in terms of SLA. Premium support is more expensive than standard support and provides you with better 24x7 support for certain types of issues and better response times. Please view the page Production Support Terms of Service to find out more.
For some Red Hat products, a cheaper self-support (also named entry-level support) support level allows you to purchase a subscription that gives you access to maintenance but not support. Self-support subscriptions are only valid for physical systems that run non-production environments.
How to optimally subscribe my complete Red Hat environment ?
When purchasing a Red Hat subscription, you agree to the Red Hat terms and conditions that stipulate that you need to subscribe all Red Hat products that you deploy. This is to prevent you from buying a single subscription and then opening support tickets for multiple different systems.
Nevertheless, you might not want to subscribe all your test and development environments. Some Red Hat customers have the option of choosing self-support subscriptions but that only works on non-production physical systems.
If you mainly have a virtualized IT environment and most of your RHEL systems are virtual, than it might be more interesting to purchase Red Hat Enterprise Linux for Virtual Datacenters subscriptions.
If that doesn't work, there is the option to deploy CentOS on your non-production systems and RHEL on your production systems. Both are binary compatible and apart from minor details, what you develop on one should work exactly the same on the other. The disadvantage of this strategy is that you need to maintain two different systems in terms of updates because they do not collect their updates from the same sources.