open-vault/website/content/docs/concepts/recovery-mode.mdx
2021-11-03 10:22:00 -04:00

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---
layout: docs
page_title: Recovery Mode
description: Recovery mode allows for doing surgery on a Vault that won't start.
---
# Recovery Mode
Vault can be started using the `-recovery` flag to bring it up in Recovery Mode.
The main purpose of recovery mode is to allow direct access to storage in case
Vault isn't starting up due to some newly discovered bug. This probably won't
be helpful without a Vault expert on hand to advise.
Differences between recovery mode and regular Vault operation:
- none of the usual subsystems run, e.g. expiration, clustering, RPCs from other nodes
- instead of a regular unseal request, unseal a node by generating a recovery token
- all requests are to `sys/raw` and are authenticated using the recovery token
## Recovery process
The usual way recovery mode is used is:
- seal or stop all nodes in the cluster
- if using Integrated Storage, run `vault status` on each node to find the highest-index ones
(this will require they be running and sealed, as if unsealed a new leader might be
elected and writes could happen, confusing the issue)
- restart the target node in recovery mode
- generate a recovery token on that node
- use the recovery token to perform sys/raw requests to repair the node
- if using Integrated Storage, reform the raft cluster as described below
## Integrated storage for HA only (ha_storage)
If Integrated Storage is used in hybrid mode (i.e. for `ha_storage`),
recovery mode will not allow for changes to the Raft data but instead allow for
modification of the underlying physical data that is associated with Vault's
storage backend. This means that the notes regarding Integrated Storage in
this doc do not apply.
## Integrated storage
With Integrated Storage, not all nodes are equal. It's possible that some
nodes are further behind - i.e. haven't applied as many Raft logs. It is
important when choosing a node to use for recovery that it has the highest
AppliedIndex found in the cluster.
Each node's AppliedIndex value can be obtained by running `vault status` against
the node sealed nodes of the cluster after bringing it down.
## Recovery tokens
Recovery tokens are issued in much the same way as root tokens are generated,
only using a different endpoint, and the Vault node must be sealed first.
Unlike root tokens, the recovery token is not persisted, so if Vault
is restarted into recovery mode a new one must be generated.
Only a single recovery token can be generated. If lost, restart Vault and
generate a new one.
## Raw requests
Requests can be issued to `sys/raw` in just the same way as in regular Vault
server mode. The only difference is that in recovery mode, `X-Vault-Token`
must contain a recovery token instead of a service or batch token.
## Reform the raft cluster
Recovery mode Vault automatically resizes the cluster to size 1. This is
necessary because the Raft protocol won't allow changes to be made without a
quorum, and in recovery mode we wish to make changes using a single node.
This means that after having used recovery mode, part of the procedure for
returning to active service must include re-forming the raft cluster. There
are two ways to do so: either delete the vault data directory on the other nodes
and re-join them to the recovered node, or use the
[Manual Recovery Using peers.json](https://www.vaultproject.io/docs/concepts/integrated-storage#manual-recovery-using-peers-json)
approach to get all nodes to agree on what nodes are part of the cluster.