Thanks for the answer. I never forget to flush, drain before shutting down Cassandra. It is a system that deals with lighter and faster data than accuracy. So rf = 2 and cl = one. Thank you again.
> On 9 Mar 2018, at 3:12 PM, Jeff Jirsa <jji...@gmail.com> wrote: > > There is no shuffling as the servers go up and down. Cassandra doesn’t do > that. > > However, rf=2 is atypical and sometime problematic. > > If you read or write with quorum / two / all, you’ll get unavailables during > the restart > > If you read or write with cl one, you’ll potentially not see data previously > written (with or without the restart). > > This is all just normal eventual consistency stuff, but be sure you > understand it - rf3 may be a better choice > > On restart, be sure you shut down cleanly - nodetool flush and then > immediately nodetool drain. Beyond that I’d expect you to be fine. > > -- > Jeff Jirsa > > >> On Mar 8, 2018, at 9:52 PM, Eunsu Kim <eunsu.bil...@gmail.com> wrote: >> >> There are currently 50000 writes per second. I was worried that the server >> downtime would be quite long during disk mount operations. >> If the data shuffling that occurs when the server goes down or up is working >> as expected, I seem to be an unnecessary concern. >> >> >>> On 9 Mar 2018, at 2:19 PM, Jeff Jirsa <jji...@gmail.com> wrote: >>> >>> I see no reason to believe you’d lose data doing this - why do you suspect >>> you may? >>> >>> -- >>> Jeff Jirsa >>> >>> >>>> On Mar 8, 2018, at 8:36 PM, Eunsu Kim <eunsu.bil...@gmail.com> wrote: >>>> >>>> The auto_snapshot setting is disabled. And the directory architecture on >>>> the five nodes will match exactly. >>>> >>>> (Cassandra/Server shutdown -> Mount disk -> Add directory to >>>> data_file_directories -> Start Cassandra) * 5 rolling >>>> >>>> Is it possible to add disks without losing data by doing the above >>>> procedure? >>>> >>>> >>>> >>>>> On 7 Mar 2018, at 7:59 PM, Rahul Singh <rahul.xavier.si...@gmail.com> >>>>> wrote: >>>>> >>>>> Are you putting both the commitlogs and the Sstables on the adds? >>>>> Consider moving your snapshots often if that’s also taking up space. >>>>> Maybe able to save some space before you add drives. >>>>> >>>>> You should be able to add these new drives and mount them without an >>>>> issue. Try to avoid different number of data dirs across nodes. It makes >>>>> automation of operational processes a little harder. >>>>> >>>>> As an aside, Depending on your usecase you may not want to have a data >>>>> density over 1.5 TB per node. >>>>> >>>>> -- >>>>> Rahul Singh >>>>> rahul.si...@anant.us >>>>> >>>>> Anant Corporation >>>>> >>>>>> On Mar 7, 2018, 1:26 AM -0500, Eunsu Kim <eunsu.bil...@gmail.com>, wrote: >>>>>> Hello, >>>>>> >>>>>> I use 5 nodes to create a cluster of Cassandra. (SSD 1TB) >>>>>> >>>>>> I'm trying to mount an additional disk(SSD 1TB) on each node because >>>>>> each disk usage growth rate is higher than I expected. Then I will add >>>>>> the the directory to data_file_directories in cassanra.yaml >>>>>> >>>>>> Can I get advice from who have experienced this situation? >>>>>> If we go through the above steps one by one, will we be able to complete >>>>>> the upgrade without losing data? >>>>>> The replication strategy is SimpleStrategy, RF 2. >>>>>> >>>>>> Thank you in advance >>>>>> --------------------------------------------------------------------- >>>>>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org >>>>>> For additional commands, e-mail: user-h...@cassandra.apache.org >>>>>> >>>> >>>> >>>> --------------------------------------------------------------------- >>>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org >>>> For additional commands, e-mail: user-h...@cassandra.apache.org >>>> >>> >>> --------------------------------------------------------------------- >>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org >>> For additional commands, e-mail: user-h...@cassandra.apache.org >>> >> >> >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org >> For additional commands, e-mail: user-h...@cassandra.apache.org >> > > --------------------------------------------------------------------- > To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org > For additional commands, e-mail: user-h...@cassandra.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org For additional commands, e-mail: user-h...@cassandra.apache.org
