Also for the new users like me, don't assume DC1 is a keyword like I did. A working example of a keyspace in EC2 is:
create keyspace test with replication_factor=3 and strategy_options = [{us-east:3}] and placement_strategy='org.apache.cassandra.locator.NetworkTopologyStrategy'; For a single DC in EC2 deployment. I felt silly afterwards, but I couldn't find official docs on the structure of strategy_options anywhere. will On Wed, Apr 13, 2011 at 5:14 PM, William Oberman <ober...@civicscience.com>wrote: > One last coda, for other noobs to cassandra like me. If you use > NetworkTopologyStrategy with replication_factor > 1, make sure you have EC2 > instance in multiple availability zones. I was doing baby steps, and tried > doing a cluster in one AZ (before spreading to multiple AZs) and was getting > the most baffling errors ("cassandra_UnavailableException"). I finally > thought to check the cassandra server logs (after debugging the client code, > firewalls, etc... painstakingly for connectivity problems), and it ends up > my cassandra cluster was considering itself "unavailable" as it couldn't > replicate as much as it wanted to. I kind of wish a different word than > "unavailable" was chosen for this error condition :-) > > will > > > On Tue, Apr 12, 2011 at 10:37 PM, aaron morton <aa...@thelastpickle.com>wrote: > >> If you can use standard + encoded I would go with that. >> >> Aaron >> >> On 13 Apr 2011, at 07:07, William Oberman wrote: >> >> Excellent to know! (and yes, I figure I'll expand someday, so I'm glad I >> found this out before digging a hole). >> >> The other issue I've been pondering is a normal column family of encoded >> objects (in my case JSON) vs. a super column. Based on my use case, things >> I've read, etc... right now I'm coming down on normal + encoded. >> >> will >> >> On Tue, Apr 12, 2011 at 2:57 PM, Jonathan Ellis <jbel...@gmail.com>wrote: >> >>> NTS is overkill in the sense that it doesn't really benefit you in a >>> single DC, but if you think you may expand to another DC in the future >>> it's much simpler if you were already using NTS, than first migrating >>> to NTS (changing strategy is painful). >>> >>> I can't think of any downsides to using NTS in a single-DC >>> environment, so that's the "safe" option. >>> >>> On Tue, Apr 12, 2011 at 1:15 PM, William Oberman >>> <ober...@civicscience.com> wrote: >>> > Hi, >>> > >>> > I'm getting closer to commiting to cassandra, and now I'm in system/IT >>> > issues and questions. I'm in the amazon EC2 cloud. I previously used >>> this >>> > forum to discover the best practice for disk layouts (large instance + >>> the >>> > two ephemeral disks in RAID0 for data + root volume for everything >>> else). >>> > Now I'm hoping to confirm bits and pieces of things I've read about for >>> > snitch/replication strategies. I was thinking of using >>> > endpoint_snitch: org.apache.cassandra.locator.Ec2Snitch >>> > >>> placement_strategy='org.apache.cassandra.locator.NetworkTopologyStrategy' >>> > (for people hitting this from the mailing list or google, I feel >>> obligated >>> > to note that the former setting is in cassandra.yaml, and the latter is >>> an >>> > option on a keyspace). >>> > >>> > But, I'm only in one region. Is using the amazon snitch/networktopology >>> > overkill given everything I have is in one DC (I believe region==DC and >>> > availability_zone==rack). I'm using multiple availability zones for >>> some >>> > level of redundancy, I'm just not yet to the point I'm using multiple >>> > regions. If someday I move to using multiple regions, would that >>> change the >>> > answer? >>> > >>> > Thanks! >>> > >>> > -- >>> > Will Oberman >>> > Civic Science, Inc. >>> > 3030 Penn Avenue., First Floor >>> > Pittsburgh, PA 15201 >>> > (M) 412-480-7835 >>> > (E) ober...@civicscience.com >>> > >>> >>> >>> >>> -- >>> Jonathan Ellis >>> Project Chair, Apache Cassandra >>> co-founder of DataStax, the source for professional Cassandra support >>> http://www.datastax.com >>> >> >> >> >> -- >> Will Oberman >> Civic Science, Inc. >> 3030 Penn Avenue., First Floor >> Pittsburgh, PA 15201 >> (M) 412-480-7835 >> (E) ober...@civicscience.com >> >> >> > > > -- > Will Oberman > Civic Science, Inc. > 3030 Penn Avenue., First Floor > Pittsburgh, PA 15201 > (M) 412-480-7835 > (E) ober...@civicscience.com > -- Will Oberman Civic Science, Inc. 3030 Penn Avenue., First Floor Pittsburgh, PA 15201 (M) 412-480-7835 (E) ober...@civicscience.com