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* conversion stage 1 * correct image paths * add sidebar title to frontmatter * docs/concepts and docs/internals * configuration docs and multi-level nav corrections * commands docs, index file corrections, small item nav correction * secrets converted * auth * add enterprise and agent docs * add extra dividers * secret section, wip * correct sidebar nav title in front matter for apu section, start working on api items * auth and backend, a couple directory structure fixes * remove old docs * intro side nav converted * reset sidebar styles, add hashi-global-styles * basic styling for nav sidebar * folder collapse functionality * patch up border length on last list item * wip restructure for content component * taking middleman hacking to the extreme, but its working * small css fix * add new mega nav * fix a small mistake from the rebase * fix a content resolution issue with middleman * title a couple missing docs pages * update deps, remove temporary markup * community page * footer to layout, community page css adjustments * wip downloads page * deps updated, downloads page ready * fix community page * homepage progress * add components, adjust spacing * docs and api landing pages * a bunch of fixes, add docs and api landing pages * update deps, add deploy scripts * add readme note * update deploy command * overview page, index title * Update doc fields Note this still requires the link fields to be populated -- this is solely related to copy on the description fields * Update api_basic_categories.yml Updated API category descriptions. Like the document descriptions you'll still need to update the link headers to the proper target pages. * Add bottom hero, adjust CSS, responsive friendly * Add mega nav title * homepage adjustments, asset boosts * small fixes * docs page styling fixes * meganav title * some category link corrections * Update API categories page updated to reflect the second level headings for api categories * Update docs_detailed_categories.yml Updated to represent the existing docs structure * Update docs_detailed_categories.yml * docs page data fix, extra operator page remove * api data fix * fix makefile * update deps, add product subnav to docs and api landing pages * Rearrange non-hands-on guides to _docs_ Since there is no place for these on learn.hashicorp, we'll put them under _docs_. * WIP Redirects for guides to docs * content and component updates * font weight hotfix, redirects * fix guides and intro sidenavs * fix some redirects * small style tweaks * Redirects to learn and internally to docs * Remove redirect to `/vault` * Remove `.html` from destination on redirects * fix incorrect index redirect * final touchups * address feedback from michell for makefile and product downloads
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| layout | page_title | sidebar_title | sidebar_current | description |
|---|---|---|---|---|
| docs | Key Rotation | Key Rotation | docs-internals-rotation | Learn about the details of key rotation within Vault. |
Key Rotation
Vault has multiple encryption keys that are used for various purposes. These keys support rotation so that they can be periodically changed or in response to a potential leak or compromise. It is useful to first understand the high-level architecture before learning about key rotation.
As a review, Vault starts in a sealed state. Vault is unsealed by providing the unseal keys. By default, Vault uses a technique known as Shamir's secret sharing algorithm to split the master key into 5 shares, any 3 of which are required to reconstruct the master key. The master key is used to protect the encryption key, which is ultimately used to protect data written to the storage backend.
To support key rotation, we need to support changing the unseal keys, master key, and the
backend encryption key. We split this into two separate operations, rekey and rotate.
The rekey operation is used to generate a new master key. When this is being done,
it is possible to change the parameters of the key splitting, so that the number of shares
and the threshold required to unseal can be changed. To perform a rekey a threshold of the
current unseal keys must be provided. This is to prevent a single malicious operator from
performing a rekey and invalidating the existing master key.
Performing a rekey is fairly straightforward. The rekey operation must be initialized with the new parameters for the split and threshold. Once initialized, the current unseal keys must be provided until the threshold is met. Once met, Vault will generate the new master key, perform the splitting, and re-encrypt the encryption key with the new master key. The new unseal keys are then provided to the operator, and the old unseal keys are no longer usable.
The rotate operation is used to change the encryption key used to protect data written
to the storage backend. This key is never provided or visible to operators, who only
have unseal keys. This simplifies the rotation, as it does not require the current key
holders unlike the rekey operation. When rotate is triggered, a new encryption key
is generated and added to a keyring. All new values written to the storage backend are
encrypted with the new key. Old values written with previous encryption keys can still
be decrypted since older keys are saved in the keyring. This allows key rotation to be
done online, without an expensive re-encryption process.
Both the rekey and rotate operations can be done online and in a highly available
configuration. Only the active Vault instance can perform either of the operations
but standby instances can still assume an active role after either operation. This is
done by providing an online upgrade path for standby instances. If the current encryption
key is N and a rotation installs N+1, Vault creates a special "upgrade" key, which
provides the N+1 encryption key protected by the N key. This upgrade key is only available
for a few minutes enabling standby instances to do a periodic check for upgrades.
This allows standby instances to update their keys and stay in-sync with the active Vault
without requiring operators to perform another unseal.