Docs: Update the Architecture Section about the Ring

[gotjosh]

The ring is one of the most complex pieces within Cortex. While the current documentation seems adequate, we could do with a more in-depth breakdown of the ring and its uses. In addition to that, a Diagram could help illustrate how it behaves in different scenarios.

In the past, I've had to refer to external sources (videos, articles) to get a better understanding of it - the intention is to have it all in one place through reference and an expanded explanation.

The plan is to build on top of #1945 to expand a bit more on this section of the documentation. I think this could help new contributors/adopters understand how Cortex works a bit better.

[pracucci]

While the current documentation seems adequate, we could do with a more in-depth breakdown of the ring and its uses.

May we write down a list of points we would like to cover?

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[pracucci]

@gotjosh Are you willing to pick up this issue?

[gotjosh]

Yes @pracucci, assign it to me.

[pracucci]

Thanks @gotjosh !

[pracucci]

We should also mention:

• You can throw away the KV store data and lifecyclers will reconstruct it
• Failure modes
• Ingesters replication set (actually the replication set of any service using the ring for sharding). Differences between ingesters, store-gateways, compactors, rulers, distributors (for limits)

[stale]

This issue has been automatically marked as stale because it has not had any activity in the past 60 days. It will be closed in 15 days if no further activity occurs. Thank you for your contributions.