>From Michael Laing - posted on the wrong thread : "We use Alain's solution as well to make major operational revisions.
We have a "red team" and a "blue team in each AWS region, so we just add and drop datacenters to get where we want to be. Pretty simple." 2015-03-31 15:50 GMT+02:00 Alain RODRIGUEZ <arodr...@gmail.com>: > IMHO, the most straight forward solution is to add cluster2 as a new DC > for mykeyspace and then drop the old DC. > > That's how we migrated to VPC (AWS) and we love this approach since you > don't have to mess with your existing cluster, plus sync is made > automatically and you can then drop your old DC safely, when you are sure. > > I put steps on this ML long time ago: > https://mail-archives.apache.org/mod_mbox/incubator-cassandra-user/201406.mbox/%3cca+vsrlopop7th8nx20aoz3as75g2jrjm3ryx119deklynhq...@mail.gmail.com%3E > Also Datastax docs: > https://www.datastax.com/documentation/cassandra/2.0/cassandra/operations/ops_add_dc_to_cluster_t.html > > "get data from cluster1, > put it to cluster2 > wipe cluster1" > > I would definitely use this method to do this (I actually did already, > multiple times). > > Up to you, I heard once that there is almost as much way of doing > operational on Cassandra as the number of operators :). You should go with > method you can be confident with. I can assure the one I propose is quite > secure. > > C*heers, > > Alain > > 2015-03-31 15:32 GMT+02:00 Serega Sheypak <serega.shey...@gmail.com>: > >> >I have to ask you if you considered doing an Alter keyspace, change RF >> The idea is dead simple: >> get data from cluster1, >> put it to cluster2 >> vipe cluster1 >> >> I understand drawbacks of streaming sstableloader approach, I need right >> now something easy. Later we consider switch to Priam since it does >> backup/restore in a right way. >> >> 2015-03-31 14:45 GMT+02:00 Alain RODRIGUEZ <arodr...@gmail.com>: >> >>> Hi, >>> >>> Despite of "I understand that it's not the best solution, I need it for >>> testing purposes", I have to ask you if you considered doing an Alter >>> keyspace, change RF > 1 for mykeyspace on cluster2 and "nodetool rebuild" >>> to add a new DC (your cluster2) ? >>> >>> In the case you go your way (sstableloader) also advice you to make a >>> snapshot (instead of just flushing) to avoid fails due to compactions on >>> your active cluster1. >>> >>> To answer your question, sstableloader is supposed to distribute >>> correctly data on the new cluster depending on your RF and topology. >>> Basically if you run sstable loader just on sstable c1.node1 my guess is >>> that you will have all the data present on c1.node1 stored on the new c2 >>> (each data to corresponding node). So if you have an RF=3 on c1, you should >>> have all the data on c2 just by running sstableloader from c1.node1, if you >>> are using RF=1 on c1, then you need to load data from c1.each_node. I >>> suppose that cluster2.nodeXXX doesn't matter and act as a coordinator. >>> >>> I never used the tool, but that's what would be "logical" imho. Wait for >>> a confirmation as I wouldn't to lead you to a failure of any kind. Also, I >>> don't know if data is also replicated directly with sstableloader or if you >>> need to repair c2 after loading data. >>> >>> C*heers, >>> >>> Alain >>> >>> 2015-03-31 13:21 GMT+02:00 Serega Sheypak <serega.shey...@gmail.com>: >>> >>>> Hi, I have a simple question and can't find related info in docs. >>>> >>>> I have cluster1 with 3 nodes and cluster2 with 5 nodes. I want to >>>> transfer whole keyspace named 'mykeyspace' data from cluster1 to cluster2 >>>> using sstableloader. I understand that it's not the best solution, I need >>>> it for testing purposes. >>>> >>>> What I'm going to do: >>>> >>>> 1. Recreate keyspace schema on cluster2 using schema from cluster1 >>>> 2. nodetool flush for mykeyspace.source_table being exported from >>>> cluster1 to cluster2 >>>> 3. >>>> >>>> Run sstableloader for each table on cluster1.node01 >>>> >>>> sstableloader -d cluster2.nodeXXX.com >>>> >>>> /var/lib/cassandra/data/mykeyspace/source_table-83f369e0d6e511e4b3a6010e8d2b68af/ >>>> >>>> What should I get as a result on cluster2? >>>> >>>> *ALL* data from source_table? >>>> >>>> or >>>> >>>> Just data stored in *partition of source_table* >>>> >>>> I'm confused. Doc says I just run this command to export table from >>>> cluster1 to cluster2, but I specify path to a part of source_table data, >>>> since other parts of table should be on other nodes. >>>> >>> >>> >> >
