sstabledowngrade

Downgrades the SSTables in the given table or snapshot to the version of OSS Apache Cassandra that is compatible with the current version of DSE.

cassandra.yaml

The location of the cassandra.yaml file depends on the type of installation:
Package installations /etc/dse/cassandra/cassandra.yaml
Tarball installations installation_location/resources/cassandra/conf/cassandra.yaml
Downgrades the SSTables in the given table or snapshot to the version of OSS Apache Cassandra™ that is compatible with the current version of DSE.
Note: The sstabledowngrade command cannot be used to downgrade system tables or downgrade DSE versions.

Synopsis

sstabledowngrade  
[--debug] 
[-h] 
[-k] 
[-b] 
[--keep-generation] 
[-o output-div] 
[--sstable-files sstable]
[-t rate-limit] 
keyspace_name 
table_name 
[snapshot_name]
Table 1. SSTable compatibility and upgrade version
DSE version SSTable sstableloader supported format-version sstableupgrade and nodetool upgradesstables supported format-version
format version
6.0.x bti aa big-ma, big-mb, big-mc, and bti-aa big-ma, big-mb, and big-mc
5.1.x big mc big-ka, big-ma, big-mb, and big-mc big-ka, big-ma, and big-mb
5.0.x
5.0.x mb big-ka, big-ma, and big-mb big-ka and big-ma
5.0.x ma big-ka and big-ma big-k* only
4.8 ka big-ka and big-jb big-j* only

Definition

The short form and long form parameters are comma-separated.

Command arguments

--debug
Display stack traces.
-h, --help
Display the usage and listing of the commands.
-k, --keep-source
Do not delete the source SSTables.
-b, --backups
Rewrite incremental backups for the given table. May not be combined with the snapshot_name option.
--keep-generation
Keep the SSTable generation. Do use with the --keep-source option.
-o, --output-dir
Rewritten files are placed in output-dir/keyspace-name/table-name-and-id.
--sstable-files
Instead of processing all SSTables in the default data directories, process only the tables specified via this option. If a single SSTable file, only that SSTable is processed. If a directory is specified, all SSTables within that directory are processed. Snapshots and backups are not supported with this option.
-t, --throughput
Set to limit the maximum disk read rate in MB/s.
keyspace_name
Keyspace name. Required. Overrides the client_encryption_options in cassandra.yaml.
table_name
Table name. Required.
snapshot_name
Snapshot name.
  • Only rewrites the specified snapshot.
  • Replaces files in the given snapshot and breaks any hard links to live SSTables.
  • Required when before attempting to restore a snapshot taken in a different DSE version than the one that is currently running.

Examples

Upgrade events table on cycling keyspace

sstabledowngrade cycling events
Found 1 sstables to rewrite.
Rewriting TrieIndexSSTableReader(path='/var/lib/cassandra/data/cycling/events-2118bc7054af11e987feb76774f7ab56/aa-1-bti-Data.db') to BIG/mc.
Rewrite of TrieIndexSSTableReader(path='/var/lib/cassandra/data/cycling/events-2118bc7054af11e987feb76774f7ab56/aa-1-bti-Data.db') to BIG/mc complete.