RedHat Enterprise Linux (RHEL) is a linux distrubution that is commonly used in production environments (Now that CentOS has been effectively rendered un-useable).

You can register for a 'free' developer subscription, which (as of 2023-04) is still free and allows up to 16 servers. This is likely to change at any time really and RedHat can of course just withdraw or make it a paid subscription and we'd be back at the point we were when CentOS was nailed.

You must RENEW this annually, and the process isn't easy or seamless. An Extract from their website…

"The Red Hat Developer Subscription for Individuals lasts for one year. When it expires, you must re-register in order to continue accessing all the support and benefits associated with the subscription. The support won't change, and it's still available at no cost for developers. This article guides you through the process to re-register and answers frequently asked questions about the process."

Wait what? So I can't renew my 'subscriptions' and all servers using my Developer Subscription will just stop receiving updates? Yes.

How to re-register for your Red Hat Developer Subscription

• Open developers.redhat.com in an Incognito window in Chrome, a Private window in Firefox, or an InPrivate window in Edge.
• Use your Red Hat login ID to sign in to the site.
• Acknowledge the provided Terms and Conditions.
• Log out of all Red Hat sites and close your browser(s).
• Wait 15 to 20 minutes, then log in to access.redhat.com/management.
• You should now see a new Red Hat Developer for Individuals Subscription on your account.

Assuming you've managed to successfully renew (re-register) your redhat developer subscription, then you will now need to re-register all your servers. On each server do the following (As root or sudo):

subscription-manager remove --all
subscription-manager unregister
subscription-manager clean

This removes all your subscriptions and de-registers with Redhat. Now we have to re-register:

subscription-manager register (you will be asked for your redhat login name and password)
subscription-manager refresh
subscription-manager attach --auto

With any luck, this will now have re-registered your servers with Redhat, and updates should start working again.