| = sstablescrub |
| |
| Fix a broken sstable. The scrub process rewrites the sstable, skipping |
| any corrupted rows. Because these rows are lost, follow this process |
| with a repair. |
| |
| ref: https://issues.apache.org/jira/browse/CASSANDRA-4321 |
| |
| Cassandra must be stopped before this tool is executed, or unexpected |
| results will occur. Note: the script does not verify that Cassandra is |
| stopped. |
| |
| == Usage |
| |
| sstablescrub <options> <keyspace> <table> |
| |
| [cols=",",] |
| |=== |
| |--debug |display stack traces |
| |
| |-h,--help |display this help message |
| |
| |-m,--manifest-check |only check and repair the leveled manifest, |
| without actually scrubbing the sstables |
| |
| |-n,--no-validate |do not validate columns using column validator |
| |
| |-r,--reinsert-overflowed-ttl |Rewrites rows with overflowed expiration |
| date affected by CASSANDRA-14092 with the maximum supported expiration |
| date of 2038-01-19T03:14:06+00:00. The rows are rewritten with the |
| original timestamp incremented by one millisecond to override/supersede |
| any potential tombstone that may have been generated during compaction |
| of the affected rows. |
| |
| |-s,--skip-corrupted |skip corrupt rows in counter tables |
| |
| |-v,--verbose |verbose output |
| |=== |
| |
| == Basic Scrub |
| |
| The scrub without options will do a snapshot first, then write all |
| non-corrupted files to a new sstable. |
| |
| Example: |
| |
| .... |
| sstablescrub keyspace1 standard1 |
| Pre-scrub sstables snapshotted into snapshot pre-scrub-1534424070883 |
| Scrubbing BigTableReader(path='/var/lib/cassandra/data/keyspace1/standard1-6365332094dd11e88f324f9c503e4753/mc-5-big-Data.db') (17.142MiB) |
| Scrub of BigTableReader(path='/var/lib/cassandra/data/keyspace1/standard1-6365332094dd11e88f324f9c503e4753/mc-5-big-Data.db') complete: 73367 rows in new sstable and 0 empty (tombstoned) rows dropped |
| Checking leveled manifest |
| .... |
| |
| == Scrub without Validation |
| |
| ref: https://issues.apache.org/jira/browse/CASSANDRA-9406 |
| |
| Use the --no-validate option to retain data that may be misrepresented |
| (e.g., an integer stored in a long field) but not corrupt. This data |
| usually doesn not present any errors to the client. |
| |
| Example: |
| |
| .... |
| sstablescrub --no-validate keyspace1 standard1 |
| Pre-scrub sstables snapshotted into snapshot pre-scrub-1536243158517 |
| Scrubbing BigTableReader(path='/var/lib/cassandra/data/keyspace1/standard1-bc9cf530b1da11e886c66d2c86545d91/mc-2-big-Data.db') (4.482MiB) |
| Scrub of BigTableReader(path='/var/lib/cassandra/data/keyspace1/standard1-bc9cf530b1da11e886c66d2c86545d91/mc-2-big-Data.db') complete; looks like all 0 rows were tombstoned |
| .... |
| |
| == Skip Corrupted Counter Tables |
| |
| ref: https://issues.apache.org/jira/browse/CASSANDRA-5930 |
| |
| If counter tables are corrupted in a way that prevents sstablescrub from |
| completing, you can use the --skip-corrupted option to skip scrubbing |
| those counter tables. This workaround is not necessary in versions 2.0+. |
| |
| Example: |
| |
| .... |
| sstablescrub --skip-corrupted keyspace1 counter1 |
| .... |
| |
| == Dealing with Overflow Dates |
| |
| ref: https://issues.apache.org/jira/browse/CASSANDRA-14092 |
| |
| Using the option --reinsert-overflowed-ttl allows a rewriting of rows |
| that had a max TTL going over the maximum (causing an overflow). |
| |
| Example: |
| |
| .... |
| sstablescrub --reinsert-overflowed-ttl keyspace1 counter1 |
| .... |
| |
| == Manifest Check |
| |
| As of Cassandra version 2.0, this option is no longer relevant, since |
| level data was moved from a separate manifest into the sstable metadata. |
