You're right Christopher, I missed the fact that with RF=3 NTS will always place a replica on us-east-1d, so in this case repair on this node would be sufficient. Thanks for clarifying!
2016-09-05 11:28 GMT-03:00 Christopher Bradford <bradfor...@gmail.com>: > If each AZ has a different rack identifier and the keyspace uses > NetworkTopologyStrategy with a replication factor of 3 then the single host > in us-east-1d *will receive 100% of the data*. This is due > to NetworkTopologyStrategy's preference for placing replicas across > different racks before placing a second replica in a rack where data > already resides. Check it out with CCM: > > > ccm node1 status > > Datacenter: us-east-1 > ===================== > Status=Up/Down > |/ State=Normal/Leaving/Joining/Moving > -- Address Load Tokens Owns (effective) Host ID > Rack > UN 127.0.0.1 98.31 KiB 1 40.0% > a887ef23-c7ea-4f7a-94a4-1ed12b1caa38 us-east-1b > UN 127.0.0.2 98.31 KiB 1 40.0% > 30152aaa-cc5e-485d-9b98-1c51f1141155 us-east-1b > UN 127.0.0.3 98.3 KiB 1 40.0% > 8e1f68f7-571e-4479-bb1f-1ed526fefa9e us-east-1c > UN 127.0.0.4 98.31 KiB 1 40.0% > 1c9b45ed-02ca-48b5-b619-a87107ff8eba us-east-1c > UN 127.0.0.5 98.31 KiB 1 40.0% > 2a33751a-c718-44fc-8442-cce9996ebc0c us-east-1d > > cqlsh> CREATE KEYSPACE replication_test WITH replication = {'class': > 'NetworkTopologyStrategy', 'us-east-1': 3}; > > > ccm node1 status replication_test > Datacenter: us-east-1 > ===================== > Status=Up/Down > |/ State=Normal/Leaving/Joining/Moving > -- Address Load Tokens Owns (effective) Host ID > Rack > UN 127.0.0.1 88.38 KiB 1 80.0% > a887ef23-c7ea-4f7a-94a4-1ed12b1caa38 us-east-1b > UN 127.0.0.2 98.31 KiB 1 20.0% > 30152aaa-cc5e-485d-9b98-1c51f1141155 us-east-1b > UN 127.0.0.3 98.3 KiB 1 80.0% > 8e1f68f7-571e-4479-bb1f-1ed526fefa9e us-east-1c > UN 127.0.0.4 98.31 KiB 1 20.0% > 1c9b45ed-02ca-48b5-b619-a87107ff8eba us-east-1c > UN 127.0.0.5 98.31 KiB 1 100.0% > 2a33751a-c718-44fc-8442-cce9996ebc0c us-east-1d > > This can be tested further with a simple table and nodetool getendpoints. > > > ccm node1 nodetool getendpoints replication_test sample bar > > 127.0.0.2 > 127.0.0.3 > 127.0.0.5 > > > ccm node1 nodetool getendpoints replication_test sample baz > > 127.0.0.1 > 127.0.0.3 > 127.0.0.5 > > > ccm node1 nodetool getendpoints replication_test sample bif > > 127.0.0.3 > 127.0.0.5 > 127.0.0.1 > > > ccm node1 nodetool getendpoints replication_test sample biz > > 127.0.0.2 > 127.0.0.3 > 127.0.0.5 > > On Fri, Sep 2, 2016 at 9:41 AM Paulo Motta <pauloricard...@gmail.com> > wrote: > >> If I understand the way replication is done, the node in us-east-1d has >> all the (data) replicas, right? >> >> No, for this to be correct, you'd need to have one DC per AZ, which is >> not this case since you have a single DC encompassing multiple AZs. Right >> now, replicas will be spread in 3 distinct AZs, which are represented as >> racks in the single NTS DC if you are using EC2*Snitch. So your best bet is >> probably to run repair -pr in all nodes. >> >> >> 2016-09-01 14:28 GMT-03:00 Li, Guangxing <guangxing...@pearson.com>: >> >>> Thanks for the info, Paulo. >>> >>> My cluster is in AWS, the keyspace has replication factor 3 with >>> NetworkTopologyStrategy in one DC which have 5 nodes: 2 in us-east-1b, 2 in >>> us-east-1c and 1 in us-east-1d. If I understand the way replication is >>> done, the node in us-east-1d has all the (data) replicas, right? If so, if >>> I do not use '-pr' option, would it be enough to run 'nodetool repair' ONLY >>> on the node in us-east-1d? In other words, does 'nodetool repair' started >>> on node in us-east-1d also cause repairs on replicas on other nodes? I am >>> seeing different answers in discussion like this >>> http://dba.stackexchange.com/questions/82414/do-you-hav >>> e-to-run-nodetool-repair-on-every-node. >>> >>> Thanks again. >>> >>> George >>> >>> On Thu, Sep 1, 2016 at 10:22 AM, Paulo Motta <pauloricard...@gmail.com> >>> wrote: >>> >>>> https://issues.apache.org/jira/browse/CASSANDRA-7450 >>>> >>>> 2016-09-01 13:11 GMT-03:00 Li, Guangxing <guangxing...@pearson.com>: >>>> >>>>> Hi, >>>>> >>>>> I have a cluster running 2.0.9 with 2 data centers. I noticed that >>>>> 'nodetool repair -pr keyspace cf' runs very slow (OpsCenter shows that the >>>>> node's data size is 39 GB and the largest SSTable size is like 7 GB so the >>>>> column family is not huge, SizeTieredCompactionStrategy is used). >>>>> Repairing >>>>> a column family on a single node takes over 5 hours. So I am wondering if >>>>> I >>>>> can use option '-local' and '-pr' together, hoping to get some speed up. >>>>> But according to documentation at https://docs.datastax.com/e >>>>> n/cassandra/2.0/cassandra/tools/toolsRepair.html '...Do not use -pr >>>>> with this option to repair only a local data center...'. Can someone tell >>>>> me the reason why we should not use options '-local' and '-pr' together? >>>>> >>>>> Thanks. >>>>> >>>>> George >>>>> >>>> >>>> >>> >>