I am running Cassandra as a Kubernetes pod . One pod is having one Cassandra container.we are running Cassandra of version 3.11.4 and auto_bootstrap set to true.I am having 5 node in production and it holds 20GB data.
Because of some maintenance activity and if I restart any Cassandra pod it is taking 30 min for bootstrap then it is coming UP and Normal state.In production 30 min is a huge time.
How can I reduce the bootup time for cassandra pod ?
Thank you !!
If you're restarting the existing node, and data is still there, then it's not a bootstrap of the node - it's just restart.
One of the potential problems that you have is that you're not draining the node before restart, and all commit logs need to be replayed on the start, and this can take a lot of time if you have a lot of data in commit log (you can just check system.log on what Cassandra is doing at that time). So the solution could be is to execute nodetool drain before stopping the node.
If the node is restarted before crash or something like, you can thing in the direction of the regular flush of the data from memtable, for example via nodetool flush, or configuring tables with periodic flush via memtable_flush_period_in_ms option on the most busy tables. But be careful with that approach as it may create a lot of small SSTables, and this will add more load on compaction process.