Unlike other databases or data engines drill doesn't store data in its own storage engine. So high availability of the data when using Drill means the storage engine needs to support high availability.
High availability can also mean that when running a query even though some of the fragments/ nodes might fail, query needs to succeed. In this scenario Drill reports an error to the user and expects the user to re-run the query. On re-running the query again, it might be successful (of-course depending upon load of the system). If a node is crashed or not responding then the ZK will not consider the node during planning stage itself. Hence, no fragments are executed on the node (and query performance might degrade in this scenario). Thanks, On Tue, Aug 28, 2018 at 9:34 AM salim achouche <sachouc...@gmail.com> wrote: > You need to clarify your definition of HA as there can be multiple faults > at play: > - A Drill cluster can handle nodes going down (and new ones joining the > cluster) > - Though, running queries (which are executed in a distributed manner) > might fail if they had minor-fragments running on a faulty node > - Similarly, Drill has some built-in resilience to network disconnects > albeit it is not always transparent (I believe, queries might fail if > network disconnect happened during a connection exchange) > > Regards, > > On Mon, Aug 27, 2018 at 10:48 PM pujari Satish <satish.ganes...@gmail.com> > wrote: > > > Hi Team, > > > > Good Morning. I am trying to do drill high avilability using Haproxy load > > balancer. > > Is drill supports for high availability ? > > > > > > please let me know in this. > > > > > > -Thanks, > > Satish > > >
