> > "one drawback: the node joins the cluster as soon as the bootstrapping > begins." > I am not sure I understand this correctly. It will get tokens, but not > load data if you combine it with autobootstrap=false. > Joining the cluster means that all other nodes become aware of the new node, and therefore it might receive reads. And yes, it will not have any data, because auto_bootstrap=false.
> How I see it: You should be able to start all the new nodes in the new DC > with autobootstrap=false and survey-mode=true. Then you should have a new > DC with nodes that have tokens but no data. Then you can start rebuild on > all new nodes. During this process, the new nodes should get writes, but > not serve reads. > Maybe you're right. > > "It turns out that join_ring=false in this scenario does not solve this > problem" > I also don't see how joing_ring would help here. (Actually I have no clue > where you would ever need that option) > The idea of join_ring=false is that other nodes are not aware of the new node, and therefore never send requests to it. The new node can then be repaired (see https://issues.apache.org/jira/browse/CASSANDRA-6961). To set up a new DC, I was hoping that you could also rebuild (instead of a repair) a new node while join_ring=false, but that seems not to work. > > > "Currently I'm trying to auto_bootstrap my new DC. The good thing is that > it doesn't accept reads from other DCs." > The joining-state actually works perfectly. The joining state is a state > where node take writes, but not serve ready. It would be really cool if you > could boot a node into the joining state. Actually, write_survey should > basically be the same. > It would be great if you could select the DC from where it's bootstrapped, similar to nodetool rebuild. I'm currently bootstrapping a node in San-Jose. It decides to stream all data from another DC in Amsterdam, while we also have another DC in San-Jose, right next to it. Streaming data across the Atlantic takes a lot more time :( > > kind regards, > Christian > > PS: I would love to see the results, if you perform any tests on the > write-survey. Please share it here on the mailing list :-) > > > > On Mon, Sep 7, 2015 at 11:10 PM, Tom van den Berge < > tom.vandenbe...@gmail.com> wrote: > >> Hi Christian, >> >> No, I never tried survey mode. I didn't know it until now, but form the >> info I was able to find it looks like it is meant for a different purpose. >> Maybe it can be used to bootstrap a new DC, though. >> >> On the other hand, the auto_bootstrap=false + rebuild scenario seems to >> be designed to do exactly what I need, except that it has one drawback: the >> node joins the cluster as soon as the bootstrapping begins. >> >> It turns out that join_ring=false in this scenario does not solve this >> problem, since nodetool rebuild does not do anything if C* is started with >> this option. >> >> A workaround could be to ensure that only LOCAL_* CL is used by all >> clients, but even then I'm seeing failed queries, because they're >> mysteriously routed to the new DC every now and then. >> >> Currently I'm trying to auto_bootstrap my new DC. The good thing is that >> it doesn't accept reads from other DCs. The bad thing is that a) I can't >> choose where it streams its data from, and b) the two nodes I've been >> trying to bootstrap crashed when they were almost finished... >> >> >> >> On Mon, Sep 7, 2015 at 10:22 PM, horschi <hors...@gmail.com> wrote: >> >>> Hi Tom, >>> >>> this sounds very much like my thread: "auto_bootstrap=false broken?" >>> >>> Did you try booting the new node with survey-mode? I wanted to try this, >>> but I am waiting for 2.0.17 to come out (survey mode is broken in earlier >>> versions). Imho survey mode is what you (and me too) want: start a node, >>> accepting writes, but not serving reads. I have not tested it yet, but I >>> think it should work. >>> >>> Also the manual join mentioned in CASSANDRA-9667 sounds very interesting. >>> >>> kind regards, >>> Christian >>> >>> On Mon, Sep 7, 2015 at 10:11 PM, Tom van den Berge <t...@drillster.com> >>> wrote: >>> >>>> Running nodetool rebuild on a node that was started with >>>> join_ring=false does not work, unfortunately. The nodetool command returns >>>> immediately, after a message appears in the log that the streaming of data >>>> has started. After that, nothing happens. >>>> >>>> Tom >>>> >>>> >>>> On Fri, Sep 12, 2014 at 5:47 PM, Robert Coli <rc...@eventbrite.com> >>>> wrote: >>>> >>>>> On Fri, Sep 12, 2014 at 6:57 AM, Tom van den Berge <t...@drillster.com> >>>>> wrote: >>>>> >>>>>> Wouldn't it be far more efficient if a node that is rebuilding itself >>>>>> is responsible for not accepting reads until the rebuild is complete? >>>>>> E.g. >>>>>> by marking it as "Joining", similar to a node that is being bootstrapped? >>>>>> >>>>> >>>>> Yes, and Cassandra 2.0.7 and above contain this long desired >>>>> functionality. >>>>> >>>>> https://issues.apache.org/jira/browse/CASSANDRA-6961 >>>>> >>>>> I presume that one can also run a rebuild in this state, though I >>>>> haven't tried. Driftx gives it an 80% chance... try it and see and let us >>>>> know? :D >>>>> >>>>> =Rob >>>>> >>>>> >>>> >>>> >>>> >>> >> >
