Is it possible that stress is overloading node 1 so it’s not recovering state properly when node 2 comes up? Have you tried running with a lower load (say 2 or 3 threads)?
Cheers Ben --- *Ben Slater* *Chief Product Officer* <https://www.facebook.com/instaclustr> <https://twitter.com/instaclustr> <https://www.linkedin.com/company/instaclustr> Read our latest technical blog posts here <https://www.instaclustr.com/blog/>. This email has been sent on behalf of Instaclustr Pty. Limited (Australia) and Instaclustr Inc (USA). This email and any attachments may contain confidential and legally privileged information. If you are not the intended recipient, do not copy or disclose its content, but please reply to this email immediately and highlight the error to the sender and then immediately delete the message. On Wed, 24 Apr 2019 at 16:28, Hiroyuki Yamada <mogwa...@gmail.com> wrote: > Hello, > > I faced a weird issue when recovering a cluster after two nodes are > stopped. > It is easily reproduce-able and looks like a bug or an issue to fix, > so let me write down the steps to reproduce. > > === STEPS TO REPRODUCE === > * Create a 3-node cluster with RF=3 > - node1(seed), node2, node3 > * Start requests to the cluster with cassandra-stress (it continues > until the end) > - what we did: cassandra-stress mixed cl=QUORUM duration=10m > -errors ignore -node node1,node2,node3 -rate threads\>=16 > threads\<=256 > * Stop node3 normally (with systemctl stop) > - the system is still available because the quorum of nodes is > still available > * Stop node2 normally (with systemctl stop) > - the system is NOT available after it's stopped. > - the client gets `UnavailableException: Not enough replicas > available for query at consistency QUORUM` > - the client gets errors right away (so few ms) > - so far it's all expected > * Wait for 1 mins > * Bring up node2 > - The issue happens here. > - the client gets ReadTimeoutException` or WriteTimeoutException > depending on if the request is read or write even after the node2 is > up > - the client gets errors after about 5000ms or 2000ms, which are > request timeout for write and read request > - what node1 reports with `nodetool status` and what node2 reports > are not consistent. (node2 thinks node1 is down) > - It takes very long time to recover from its state > === STEPS TO REPRODUCE === > > Is it supposed to happen ? > If we don't start cassandra-stress, it's all fine. > > Some workarounds we found to recover the state are the followings: > * Restarting node1 and it recovers its state right after it's restarted > * Setting lower value in dynamic_snitch_reset_interval_in_ms (to 60000 > or something) > > I don't think either of them is a really good solution. > Can anyone explain what is going on and what is the best way to make > it not happen or recover ? > > Thanks, > Hiro > > --------------------------------------------------------------------- > To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org > For additional commands, e-mail: user-h...@cassandra.apache.org > >
