Take a snapshot

Snapshots are taken per node using the nodetool snapshot command. To take a global snapshot, run the command with a parallel SSH utility, such as pssh.

A snapshot first flushes all in-memory writes to disk, then makes a hard link of the SSTable files for each keyspace. You must have enough free disk space on the node to accommodate making snapshots of your data files. A single snapshot requires little disk space. However, snapshots can cause your disk usage to grow more quickly over time because a snapshot prevents old obsolete data files from being deleted. After the snapshot is complete, you can move the backup files to another location, or you can leave them in place.

Run nodetool cleanup to ensure that invalid replicas are removed:
```
nodetool cleanup cycling
```
Run the nodetool snapshot command, specifying the keyspace to snapshot and any necessary connection options, such as the hostname or JMX port.

For example:
```
nodetool snapshot -t cycling_2017-3-9 cycling
```
For tarball installations, you must run this command from the INSTALL_DIRECTORY/resources/cassandra/bin directory.
Get the Snapshot directory from the output:
```
Requested creating snapshot(s) for [cycling] with snapshot name [2015.07.17] and options {skipFlush=false}
Snapshot directory: cycling_2017-3-9
```
The Snapshot directory is the name of a subdirectory containing the snapshot files. The complete path to the snapshot directory is /data/KEYSPACE_NAME/TABLE_NAME-UUID/snapshots/SNAPSHOT_NAME.

If the keyspace contains multiple tables, the snapshot process creates multiple snapshot directories with the given Snapshot directory name. For example, the following path is for a table named cyclist_name in the cycling keyspace:
```
data/cycling/cyclist_name-9e516080f30811e689e40725f37c761d/snapshots/cycling_2017-3-9
```
To restore from a snapshot, get the table schema file from the snapshot directory.

Within each snapshot directory, there are multiple data files with the extension .db and a schema.cql file that contains the full CQL statement to create the table. For example:
```
manifest.json
mc-1-big-CompressionInfo.db
mc-1-big-Data.db
mc-1-big-Digest.crc32
mc-1-big-Filter.db
mc-1-big-Index.db
mc-1-big-Statistics.db
mc-1-big-Summary.db
mc-1-big-TOC.txt
schema.cql
```

Take a snapshot

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