docker - Can I have some keyspaces replicated to some nodes? -


i trying build multiple api want store data cassandra. designing if have multiple hosts but, hosts envisioned of 2 types: trusted , non-trusted.

because of have data don't want end replicated on group of hosts rest of data replicated everywhere.

i considered making node public data , 1 protected data require trusted hosts run 2 nodes , complicate way api interacts data.

i building in docker container also, expect there frequent node creation/destruction both trusted , not trusted.

i want know if possible use keyspaces in order achieve required replication strategy.

you have 2 datacenters 1 having public data , other private data. can configure keyspace replication replicate data 1 (or both) dcs. see docs on replication networktopologystrategy

however there security concerns here since nodes need able reach 1 via gossip protocol , client applications might need contact both dcs different reads , writes.

i suggest configuring security perhaps ssl starters , perhaps internal authentication. note kerberos supported might complex need @ least now.

you may consider taking @ firewall docs see ports used between nodes , clients know ones lock down.

finally above poster mentions, destruction / creation of nodes not practice. cassandra designed able grow / shrink cluster while running, can costly operation involves not streaming data / node being removed / added other nodes shuffling around token ranges rebalance.

you can run nodes in docker containers, note need take care not things several containers accessing same physical resources. cassandra quite sensitive io latency example, several containers sharing same physical disk might render performance problems.


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