Re: moving data from single node cassandra

Thanks Maki :) I copied the existing var folder to the new hardisk and changes the path to the data directories in the storage-config.xml I was successfully able to connect with cassandra and read the data that was shifted to the new location. On Fri, Mar 18, 2011 at 6:33 AM, Maki Watanabe

Re: super_column.name?

Are you using thrift 0.5 as downloaded from there: http://incubator.apache.org/thrift/download/ ? On Thu, Mar 17, 2011 at 10:20 PM, Michael Fortin mi...@m410.us wrote: Thanks for the response, sorry if my initial question wasn't clear. When using thrift, I call client.get_slice(keyBytes,

[0.7.2] Compacting exception

Hi ! I have run with Cassandra 0.7.2 out of disc space and after moving to bigger partition I experience compaction failures[1]. 1) I suspect one of SSTables is broken. If I am right how can I find which one exactly ? 2) Knowing which one is broken is it safe to stop Cassandra, remove

avro cassandra example

hi all, i am searching for a working example of cassandra using avro as rpc client, still no luck... , pl share if any one have worked on it... any help or pointers ??? regards Sagar Are you exploring a Big Data Strategy ? Listen to this recorded webinar on

Re: avro cassandra example

Avro support for client rpc has been dropped (It was never official anyway), so it is strongly discouraged to try using it. -- Sylvain 2011/3/18 Sagar Kohli sagar.ko...@impetus.co.in: hi all, i am searching for a working example of cassandra using avro as rpc client, still no luck... , pl

Re: [0.7.2] Compacting exception

Upgrade to 0.7.4 and run nodetool scrub (then watch the log). If it reports bad rows then run repair post-scrub. On Fri, Mar 18, 2011 at 6:44 AM, Mateusz Korniak mateusz-li...@ant.gliwice.pl wrote: Hi ! I have run with Cassandra 0.7.2 out of disc space and after moving to bigger partition I

Re: map reduce job over indexed range of keys

On Thu, 2011-02-24 at 19:45 -0500, Matt Kennedy wrote: Right, so I'm interpreting silence as a confirmation on all points. I opened: https://issues.apache.org/jira/browse/CASSANDRA-2245 https://issues.apache.org/jira/browse/CASSANDRA-2246 I think

EC2 - 2 regions

Hello, I am trying to setup a cassandra cluster across regions. For testing I am keeping it simple and just having one node in US-EAST (say ec2-1-2-3-4.compute-1.amazonaws.com) and one node in US-WEST (say ec2-2-2-3-4.us-west-1.compute.amazonaws.com). Using Cassandra 0.7.4 The one in east

HintedHandoff increases in read?

Hi, When I looking at countPendingHints in HintedHandoffManager via jmx, I found that pending hints increases even when my cluster handles only reads with quorum from clients. The count decreases when I see it in long period (e.g., in an hour). But it can increase in several thousands in short

Cassandra London UG meetup Monday

Hi all, Anyone based in the UK may be interested in our user group meetup on Monday. We will have talks on Hadoop integration and some performance data related to this. Please come along if you'd like to meet other people using Cassandra or would like to learn more.

Re: EC2 - 2 regions

Hi AJ, I'd suggest getting to a multi-region cluster step-by-step. First, get 2 nodes running in the same availability zone. Make sure that works properly. Second, add a node in a separate availability zone, but in the same region. Make sure that's working properly. Third, add a node that's

Re: EC2 - 2 regions

Thats exactly what I am doing. I was able to do the first two scenarios without any issues (i.e. 2 nodes in same availability zone. Followed by an additional node in a different zone but same region) I am stuck at the third scenario of separate regions. (I did read the Cassandra nodes on EC2 in

Re: EC2 - 2 regions

From the us-west instance, are you able to connect to the us-east instance using telnet on port 7000 and 9160? If not, then you need to open those ports for communication (via your Security Group) Dave Viner On Fri, Mar 18, 2011 at 10:20 AM, A J s5a...@gmail.com wrote: Thats exactly what I am

Re: EC2 - 2 regions

have you confirmed connectivity through the different security groups and that you're not being blocked between region:port -- region: port ? On Fri, Mar 18, 2011 at 6:20 PM, A J s5a...@gmail.com wrote: Thats exactly what I am doing. I was able to do the first two scenarios without any

Re: EC2 - 2 regions

I am able to telnet from one region to another on 7000 port without issues. (I get the expected Connected to .Escape character is '^]'.) Also I am able to execute cassandra client on 9160 port from one region to another without issues (this is when I run cassandra separately on each region

Re: EC2 - 2 regions

Just to add, all the telnet (port 7000) and cassandra-cli (port 9160) connections are done using the public DNS (that goes like ec2-.compute.amazonaws.com) On Fri, Mar 18, 2011 at 1:37 PM, A J s5a...@gmail.com wrote: I am able to telnet from one region to another on 7000 port without

Active / Active Data Center and RF

When in active/active data center how to decide right replication factor? Client may connect and request for the information from either data center so if locally it's RF=3 then in multiple data center should it be RF=6 in active/active? Or what happens if it's RF=3 with network toplogy and 2

Working backwards from production to staging/dev

Hi everyone, I was on the mailing list back in December/January, asking questions about rebalancing some nodes, etc. We currently have a ring of 3 systems, redundancy set to 2, and all is well. We'd like to snapshot our ring and build a new development/staging node from it (the old dev node

Re: Working backwards from production to staging/dev

That should work, but if you have the disk space it's a lot simpler to just copy all the data files from each machine to a target out of the cluster, then have the target run cleanup. On Fri, Mar 18, 2011 at 1:07 PM, ian douglas i...@armorgames.com wrote: Hi everyone, I was on the mailing list

Undead rows after nodetool compact

This has been discussed once, but I don't remember the outcome. I insert a row and then delete the key immediately. I then run nodetool compact. In cassanra-cli, list cf still return 1 empty row. This is not a showstopper but damn unpretty. Is there a way to make deleted rows go, immediately? --

Re: On 0.6.6 to 0.7.3 migration, DC-aware traffic and minimising data transfer

Right. Only subtlety is the system keyspace; cleanest is to just start from scratch there (which means rebuilding the schema) but you could also start with a copy of an existing node's (just one) and start up with -Dcassandra.load_ring_state=false. On Fri, Mar 18, 2011 at 2:29 PM, Jeremiah

Re: super_column.name?

Hi, Just thought I follow up and mention that I was able to fix it. I was calling super_column.name in scala, which was accessing the name field in the SuperColumn class, and not actually calling getName(). Thanks for the feedback, it helped. M!ke On Mar 18, 2011, at 4:16 AM, Sylvain

Re: Undead rows after nodetool compact

http://wiki.apache.org/cassandra/FAQ#range_ghosts On Fri, Mar 18, 2011 at 3:12 PM, buddhasystem potek...@bnl.gov wrote: This has been discussed once, but I don't remember the outcome. I insert a row and then delete the key immediately. I then run nodetool compact. In cassanra-cli, list cf

Re: [0.7.2] Compacting exception

On Friday 18 of March 2011, Jonathan Ellis wrote: Upgrade to 0.7.4 and run nodetool scrub (then watch the log). Unfortunately nodetool scrub fails with: WARN [CompactionExecutor:1] 2011-03-19 00:34:53,511 CompactionManager.java (line 607) Non-fatal error reading row (stacktrace follows)

Reading whole row vs a range of columns (pycassa)

Is there is noticeable difference in speed between reading the whole row through Pycassa, vs a range of columns? Both rows and columns are pretty slim. -- View this message in context:

0.6.5 OOM during high read load

Dear experts, :) Our application triggered an OOM error in Cassandra 0.6.5 by reading the same 1.7MB column repeatedly (~80k reads). I analyzed the heap dump, and it looks like the column value was queued 5400 times in an OutboundTcpConnection destined for the Cassandra instance that received the

Re: Cassandra London UG meetup Monday

Hello Dave, I am in Australia and was wondering if this group could do a phone hookup? Ash On 19/03/2011, at 2:25 AM, Dave Gardner dave.gard...@visualdna.com wrote: Hi all, Anyone based in the UK may be interested in our user group meetup on Monday. We will have talks on Hadoop

Disabling compaction?

Hey everyone, Is there a way to prevent cassandra from compacting while it is running? I am having to do some scrub+sstable2json-json2sstable magic, and I don't want the data changing at all while I am in the process. Thanks, Jason

Re: Disabling compaction?

Got my answer from the #cassandra channel: I can set max_compaction_threshold to 0 to prevent compaction from occurring while I rebuild everything. Thanks! Jason Harvey On Mar 18, 5:45 pm, Jason Harvey alie...@gmail.com wrote: Hey everyone, Is there a way to prevent cassandra from

Error connection to remote JMX agent! on nodetool

Hi everyone I am still new to Cassandra, Thrift. But anyway Cassandra 0.7.4, Thrift 0.5.0 are working on java 1.6.0.18 of Debian 5.0.7.at single node. Then I had to try and check multi node on 2 servers. (JVM_PORT=10036 on /etc/cassandra-env.sh) I modified /etc/cassandra/cassandra.yaml as

Optimizing a few nodes to handle all client connections?

Hola everyone, I have been considering making a few nodes only manage 1 token and entirely dedicating them to talking to clients. My reasoning behind this is I don't like the idea of a node having a dual-duty of handling data, and talking to all of the client stuff. Is there any merit to this

Re: Optimizing a few nodes to handle all client connections?

Are you saying you dont like the idea of the co-ordinator node being in the same ring? if yes have you looked at the cassandra fat client in contrib? Regards, /VJ On Fri, Mar 18, 2011 at 6:55 PM, Jason Harvey alie...@gmail.com wrote: Hola everyone, I have been considering making a few

Re: Reading whole row vs a range of columns (pycassa)

As I'm working on this further, I want to understand this: Is it advantageous to flatten data in blocks (strings) each containing a series of objects, if I know that a serial object read is often likely, but don't want to resort to OPP? I worked out the optimal granularity, it seems. Is it better