DataStax Academy FAQ

DataStax Academy migrated to a new learning management system (LMS) in July 2020. We are also moving to a new Cassandra Certification process so there are changes to exam bookings, voucher system and issuing of certificates.

Check out the Academy FAQ pages for answers to your questions:


question

amit82ocp_172818 avatar image
amit82ocp_172818 asked ·

Insert/nodetool flush is not genrating sstables.

Hello All, While working on DS201 6.X course, Compaction exercise says that perform insert and then nodetool flush which would generate sstable after each attempt of insert and flush however I can see no sstables getting generated
10:51 AM
Can anyone help me to understand what this is not generating sstables
sstables.
1 comment
10 |1000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 1.0 MiB each and 10.0 MiB total.

How many nodes do you have setup for the course? If you have more than one, you would need to run nodetool flush on all nodes. Depending on your RF, the data may not live on the node that you are running your commands from.

1 Like 1 · ·
Erick Ramirez avatar image
Erick Ramirez answered ·

@amit82ocp_172818 as @@brasco --Donnie Roberson-- indicated, you won't necessarily have SSTables if the node you flushed is not a replica of the data you inserted. Say you had a 3-node cluster and a keyspace with a replication factor of 3. In this configuration, all 3 nodes would be replicas so flushing on any node will have SSTables written to disk.

If you had a 3-node cluster but the keyspace only has a replication factor of 1, you would need to run nodetool getendpoints to determine the owner of the partition and run a flush on that node to see SSTables on disk. Cheers!

1 comment Share
10 |1000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 1.0 MiB each and 10.0 MiB total.

Hello @Erick Ramirez, thanks for answer on this.

I have find the endpoints of keyspace and able to get the sstables on disk.

Thanks for your help on this.


Regards,

Amit

0 Likes 0 · ·
amit82ocp_172818 avatar image
amit82ocp_172818 answered ·

Hello @Erick Ramirez, thanks for answer on this.

I have find the endpoints of keyspace and able to get the sstables on disk.

Thanks for your help on this.


Regards,

Amit


1 comment Share
10 |1000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 1.0 MiB each and 10.0 MiB total.

@amit82ocp_172818 Just a friendly note that you need to comment instead of "writing an answer" so other users don't confuse this as an answer in the future. Please edit and re-post. Cheers!

0 Likes 0 · ·