sstablescrub for unreadable sstables?

[David Paulsen <dj...@gmail.com>]

Two questions really:

1) Is there a way to search the archives
https://mail-archives.apache.org/mod_mbox/cassandra-user/ or another better
approach to searching for Cassandra answers such as #2?

2) I have the following error in /var/log/cassandra/cassandra.log -
cassandra dies after "service cassandra start"

This is Cassandra 2.1.8 running on RHEL 6.6, in a docker container.

ERROR 12:16:09 Detected unreadable sstables
/data/cassandra_saved_caches/system-schema_keyspaces-b0f2235744583cdb9631c43e59ce3676-KeyCache-b.db,/data/cassandra_saved_caches/system-local-7ad5
4392bcdd35a684174e047860b377-KeyCache-b.db,/data/cassandra_saved_caches/system-schema_columns-296e9c049bec3085827dc17d3df2122a-KeyCache-b.db,/data/cassandra_saved_caches/system-sstable_activ
ity-5a1ff267ace03f128563cfae6103c65e-KeyCache-b.db,/data/cassandra_saved_caches/system-schema_columnfamilies-45f5b36024bc3f83a3631034ea4fa697-KeyCache-b.db,
please check NEWS.txt and ensure
that you have upgraded through all required intermediate versions, running
upgradesstables

This is Cassandra 2.1.8 running on RHEL 6.6, in a docker container - single
node "cluster".
Fortunately, this is an experimental system, not production (and actually
running in a VM that experienced a couple of transient disconnects to its
datastore, likely having ill effect on /data.)
I'd really *hate* to see this happen in production!  (But then, in
production, I should have some pretty resilient storage for
data_file_directories and commitlog_directory.)

Is this a case where sstablescrub might be useful?  If so, I've only vague
ideas about what arguments to supply for <keyspace> and <column_family>.

Re: sstablescrub for unreadable sstables?

[Jeff Jirsa <je...@crowdstrike.com>]

For key cache files (which you have below – note ‘cassandra_saved_caches’ and -KeyCache– ), the safest thing to do is to simply remove them (move them aside or delete them). They’re simple caches, and they’ll be recreated shortly after starting.

- Jeff

From:  David Paulsen
Reply-To:  "user@cassandra.apache.org"
Date:  Tuesday, August 18, 2015 at 12:26 PM
To:  "user@cassandra.apache.org"
Subject:  sstablescrub for unreadable sstables?

Two questions really:

1) Is there a way to search the archives https://mail-archives.apache.org/mod_mbox/cassandra-user/ or another better approach to searching for Cassandra answers such as #2?

2) I have the following error in /var/log/cassandra/cassandra.log - cassandra dies after "service cassandra start"

This is Cassandra 2.1.8 running on RHEL 6.6, in a docker container.

ERROR 12:16:09 Detected unreadable sstables /data/cassandra_saved_caches/system-schema_keyspaces-b0f2235744583cdb9631c43e59ce3676-KeyCache-b.db,/data/cassandra_saved_caches/system-local-7ad5
4392bcdd35a684174e047860b377-KeyCache-b.db,/data/cassandra_saved_caches/system-schema_columns-296e9c049bec3085827dc17d3df2122a-KeyCache-b.db,/data/cassandra_saved_caches/system-sstable_activ
ity-5a1ff267ace03f128563cfae6103c65e-KeyCache-b.db,/data/cassandra_saved_caches/system-schema_columnfamilies-45f5b36024bc3f83a3631034ea4fa697-KeyCache-b.db, please check NEWS.txt and ensure
that you have upgraded through all required intermediate versions, running upgradesstables

This is Cassandra 2.1.8 running on RHEL 6.6, in a docker container - single node "cluster". 
Fortunately, this is an experimental system, not production (and actually running in a VM that experienced a couple of transient disconnects to its datastore, likely having ill effect on /data.)
I'd really hate to see this happen in production!  (But then, in production, I should have some pretty resilient storage for data_file_directories and commitlog_directory.)

Is this a case where sstablescrub might be useful?  If so, I've only vague ideas about what arguments to supply for <keyspace> and <column_family>.