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Warning:CockroachDB v20.2 is no longer supported. For more details, see the Release Support Policy.
cockroach debug ballast command creates a large, unused file that you can place in a node's storage directory. In the case that a node runs out of disk space and shuts down, you can delete the ballast file to free up enough space to be able to restart the node.
- Do not run
cockroach debug ballastwith a unix
rootuser. Doing so brings the risk of mistakenly affecting system directories or files.
- Do not name the target file similar to a block device in
/dev. Doing so brings the risk of mistyping a
/devprefix into the command and thereby corrupting a filesystem.
- In addition to placing a ballast file in each node's storage directory, it is important to actively monitor remaining disk space.
- Ballast files may be created in many ways, including the standard
cockroach debug ballastuses the
fallocatesystem call when available, so it will be faster than
cockroach debug command has a few subcommands, users are expected to use only the
debug subcommands are useful only to CockroachDB's developers and contributors.
Create a ballast file:
$ cockroach debug ballast [path to ballast file] [flags]
$ cockroach debug ballast --help
||The amount of space to fill, or to leave available, in a node's storage directory via a ballast file. Positive values equal the size of the ballast file. Negative values equal the amount of space to leave after creating the ballast file. This can be a percentage (notated as a decimal or with %) or any bytes-based unit, for example:
Create a 1GB ballast file (default)
$ cockroach debug ballast cockroach-data/ballast.txt
Create a ballast file of a different size
$ cockroach debug ballast cockroach-data/ballast.txt --size=2GB