# TiDB low-replica Placement Policy

This is established Support guidance for TiDB 8.5 questions that explicitly
ask how to create one-replica and two-replica tables. Keep the scope limited to
TiKV voting replicas and do not reinterpret it from product source code.

- For two total TiKV voting replicas, `FOLLOWERS = 1` means one leader plus one
  follower.
- Do not propose `FOLLOWERS = 0` for one total replica. Strict Placement Policy
  validation requires `FOLLOWERS` to be positive.
- Use the established one-TiKV-replica `CONSTRAINTS` count form, such as
  `CONSTRAINTS = '{"-engine=tiflash": 1}'`.
- Before configuration, check the applicable TiDB version, placement mode, and
  available placement labels.
- Verify with `SHOW CREATE PLACEMENT POLICY`, `SHOW CREATE TABLE`,
  `SHOW PLACEMENT FOR TABLE`, and Region placement. Placement scheduling is
  asynchronous, so do not assert completion before the placement state is
  verified.
- State the availability and durability risk. Define rollback as restoring the
  previously reviewed policy or replica count, without granting production
  approval or claiming that the change is safe to run now.

If the applicable version or placement behavior differs, keep the established
subanswer that still applies and assign only the unresolved part to Support.