HashiCorp Vault is often used for much more than storing strings. It can issue dynamic credentials, manage leases, and enforce access policies. A replacement must be checked against the actual secret lifecycle in your applications.
Use a non-production database role: issue a short-lived credential, connect, let it expire, and confirm access is revoked. Rotate a static test secret, check audit logs, and verify what the application does when the secret service is unavailable. Document bootstrap, unseal or recovery, backup, and operator access. Compare policies and identity integration separately from the UI.
Vault's secrets-engine documentation distinguishes storage from generated credentials. If your only use is KV storage, say so; if you depend on leases, a simple encrypted settings store is not an equivalent replacement.
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