nodetool snapshot

Take a snapshot of one or more keyspaces, or of a table, to backup data.

Synopsis

nodetool <options> snapshot
     ( -cf <table> | --column-family <table> )
     (-kc <ktlist> | --kc.list <ktlist> | -kt <ktlist> | --kt-list <ktlist>)
     (-sf | --skip-flush) 
     (-t <tag> | --tag <tag> )
     -- ( <keyspace>  |  <keyspace> ... )

Cassandra tarball installations:

installation_location/cassandra/bin

Table 1. Options
Short	Long	Description
`-h`	`--host`	Hostname or IP address.
`-p`	`--port`	Port number.
`-pwf`	`--password-file`	Password file path.
`-pw`	`--password`	Password.
`-u`	`--username`	Remote JMX agent username.
`-cf table`	`--column-family table`	Name of the `table` to snapshot. You must specify one and only one keyspace.
	`--table table`	Name of the `table` to snapshot. You must specify one and only one keyspace.
`-kc ktlist`	`--kc.list ktlist`	The list of keyspace.tables to snapshot. Requires list of keyspaces.
`-kt ktlist`	`--kt-list` `ktlist`	The list of keyspace.tablea to snapshot. Requires list of keyspaces.
`-sf`	`--skip-flush`	Executes the snapshot without flushing the tables first (Cassandra 3.4 and later).
`-t`	`--tag`	Name of snapshot.
`keyspace`	One or more optional keyspace names, separated by a space. Default: all keyspaces
`--`		Separates an option from an argument that could be mistaken for a option.

Description

Use this command to back up data using a snapshot. See the examples below for various options.

Cassandra flushes the node before taking a snapshot, takes the snapshot, and stores the data in the snapshots directory of each keyspace in the data directory. If you do not specify the name of a snapshot directory using the -t option, Cassandra names the directory using the timestamp of the snapshot, for example 1391460334889. Follow the procedure for taking a snapshot before upgrading Cassandra. When upgrading, backup all keyspaces.

Example: All keyspaces

Take a snapshot of all keyspaces on the node. On Linux, in the Cassandra bin directory, for example:

nodetool snapshot

The following message appears:

Requested creating snapshot(s) for [all keyspaces] with snapshot name [1391464041163]
Snapshot directory: 1391464041163

Because you did not specify a snapshot name, Cassandra names snapshot directories using the timestamp of the snapshot.

Example: Single keyspace snapshot

Assuming you created the keyspace cycling, took a snapshot of the keyspace and named the snapshot 2015.07.17.:

nodetool snapshot -t 2015.07.17 cycling

The following output appears:

Requested creating snapshot(s) for [cycling] with snapshot name [2015.07.17]
Snapshot directory: 2015.07.17

Assuming the cycling keyspace contains two tables, cyclist_name and upcoming_calendar, taking a snapshot of the keyspace creates multiple snapshot directories named 2015.07.17. A number of .db files containing the data are located in these directories. For example, from the installation directory:

cd data/data/cycling/cyclist_name-a882dca02aaf11e58c7b8b496c707234/snapshots/2015.07.17
$ ls

la-1-big-CompressionInfo.db  la-1-big-Index.db       la-1-big-TOC.txt
la-1-big-Data.db             la-1-big-Statistics.db  la-1-big-Digest.adler32
la-1-big-Filter.db           la-1-big-Summary.db  manifest.json

cd data/data/cycling/cyclist_name-a882dca02aaf11e58c7b8b496c707234/snapshots/2015.07.17
$ ls

la-1-big-CompressionInfo.db  la-1-big-Index.db       la-1-big-TOC.txt
la-1-big-Data.db             la-1-big-Statistics.db  la-1-big-Digest.adler32
la-1-big-Filter.db           la-1-big-Summary.db  manifest.json

Example: Multiple keyspaces snapshot

Assuming you created a keyspace named mykeyspace in addition to the cycling keyspace, take a snapshot of both keyspaces.

nodetool snapshot mykeyspace cycling

The following message appears:

Requested creating snapshot(s) for [mykeyspace, cycling] with snapshot name [1391460334889]
Snapshot directory: 1391460334889

Example: Single table snapshot

Take a snapshot of only the cyclist_name table in the cycling keyspace.

nodetool snapshot --table cyclist_name cycling

Requested creating snapshot(s) for [cycling] with snapshot name [1391461910600]
Snapshot directory: 1391461910600

Cassandra creates the snapshot directory named 1391461910600 that contains the backup data of cyclist_name table in data/data/cycling/cyclist_name-a882dca02aaf11e58c7b8b496c707234/snapshots, for example.

Example: List of different keyspace.tables snapshot

Take a snapshot of several tables in different keyspaces, such as the cyclist_name table in the cycling keyspace and the sample_times table in the test keyspace. The keyspace.table list should be comma-delimited with no spaces.

nodetool snapshot -kt cycling.cyclist_name,test.sample_times

Requested creating snapshot(s) for [cycling.cyclist_name,test.sample_times] with snapshot name [1431045288401]
Snapshot directory: 1431045288401