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DBA-C0058 · Configuration & Tuning

Redis Eviction Policies Explained

Pick one Redis eviction policy as a note. Do not apply it. Do not run FLUSHALL.

Updated 25 October 2026 · Explainer

This is an original planning guide. It is not a vendor manual, an official standard, or legal advice. Example addresses use documentation ranges. Review every command before you paste it.

What this hour is for

The selector names a policy from the choice you make. The note says what that policy may drop. You do not apply it on this page.

Do not run FLUSHALL. Do not change maxmemory on a live instance during the reading. protected-mode stays on.

192.0.2.10, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. example.com is a documentation name. A sample password is replaced. It is not a password you keep.

The change you can finish

Apply nothing while you are writing the note. When the lab window opens, it is one change on the database named in the ticket. Read the draft, then the database, then decide.

Rollback is the backup, the file, or the snapshot you saved first. You do not invent a rollback after the only copy is gone.

  1. Write the policy name.
  2. Write what it may drop.
  3. Do not apply it.
  4. Do not run FLUSHALL.
  5. Stop.

Mistakes that outlive the statement

Redis Eviction Policies Explained goes wrong in a small set of ways. The list is here so the ticket can forbid them before the window.

Decisions to write down

One decision for Redis Eviction Policies Explained: The policy is written. Nothing was applied. FLUSHALL was not run. And protected-mode stays on.

Checks before you call it done

Confirm this before you call the change done: The instance is written. The policy is written. Nothing was applied. FLUSHALL was not run. And the database is yours. If one of those fails, stop.

# Eviction is a note.
# Do not apply it during the reading.
# Do not run FLUSHALL.
# protected-mode stays on.

Before you leave the database

Redis Eviction Policies Explained ends when the database in the prompt is the database in the ticket. If it is not, you are on the wrong database. Stop.

The draft stays a draft until a person has read the names in it. A generator does not log into the database. You delete a line that names a host, a database, or an account you did not write down.

192.0.2.10, 198.51.100.0/24, 203.0.113.0/24, and 2001:db8::/32 are documentation. example.com is a documentation name. They belong in the note. They are not values you leave on a database because a draft included them.

prompt-for-this is a reminder that a secret is missing. It is not a password, a key, or a token you save in the ticket or in git. A sample password in a draft is replaced. It is not a password you keep.

One change is the window. If two things move and the result is wrong, you will not know which one did it.

If the same step fails twice, stop for the day. Restore the copy you took first.

A second person reads the database name and the change aloud. If they cannot find them in the ticket, the note is not done.

This page is a planning guide. It is not a vendor manual, not an official standard, and not permission to touch a database you do not administer. You do not disable authentication, a firewall, or TLS to make a check pass.

Tools for this guide

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More in this cluster

The pillar for this page, and the next published pages filed with it.