github.com/hugorut/terraform@v1.1.3/website/docs/language/state/locking.mdx (about) 1 --- 2 page_title: 'State: Locking' 3 description: >- 4 Terraform stores state which caches the known state of the world the last time 5 Terraform ran. 6 --- 7 8 # State Locking 9 10 If supported by your [backend](/language/settings/backends), Terraform will lock your 11 state for all operations that could write state. This prevents 12 others from acquiring the lock and potentially corrupting your state. 13 14 State locking happens automatically on all operations that could write 15 state. You won't see any message that it is happening. If state locking fails, 16 Terraform will not continue. You can disable state locking for most commands 17 with the `-lock` flag but it is not recommended. 18 19 If acquiring the lock is taking longer than expected, Terraform will output 20 a status message. If Terraform doesn't output a message, state locking is 21 still occurring if your backend supports it. 22 23 Not all backends support locking. The 24 [documentation for each backend](/language/settings/backends) 25 includes details on whether it supports locking or not. 26 27 ## Force Unlock 28 29 Terraform has a [force-unlock command](/cli/commands/force-unlock) 30 to manually unlock the state if unlocking failed. 31 32 **Be very careful with this command.** If you unlock the state when someone 33 else is holding the lock it could cause multiple writers. Force unlock should 34 only be used to unlock your own lock in the situation where automatic 35 unlocking failed. 36 37 To protect you, the `force-unlock` command requires a unique lock ID. Terraform 38 will output this lock ID if unlocking fails. This lock ID acts as a 39 [nonce](https://en.wikipedia.org/wiki/Cryptographic_nonce), ensuring 40 that locks and unlocks target the correct lock.