Re: Is it safe to remove (pid file folder) /var/run/cassandra

I've verified that problem is solvable by deleting * /var/run/cassandra*folder on my test server. Should I remove the pid folder from my new production server ? On Wed, Mar 19, 2014 at 10:54 AM, user 01 wrote: > Is it safe to remove (pid file folder)* /var/run/cassandra* if I think it > has go

Is it safe to remove (pid file folder) /var/run/cassandra

Is it safe to remove (pid file folder)* /var/run/cassandra* if I think it has got wrong permissions, will it be recreated by process as before ? folder permissions seem to be incorrect immediately after I installed dsc20 & due to this "sudo service cassandra start" fails saying - "* could not acc

Setting up Cassandra across private network

I'm currently using Cassandra 1.23 and I'm trying to set up a cluster on the private network, so that nodes can communicate through eth4 inet address instead of eth0 inet address. My current yaml file specify eth4 address in the seed field. However the the rpc address is set to 0.0.0.0. Both liste

Multi-site Active-Active replication - Maintenance Commands

Hi all, We currently run a script that runs the following on our separate clusters each night. The script operates on 3 nodes (out of 9) a night to minimize impact to the cluster. repair -pr compact cleanup These separate clusters are going to start replicating between each other within a

Re: Multi-site Active-Active replication - Preparing Sites - Cluster Name and Snitch

Thanks Jonathan, points taken onboard. I'll be testing the GossipingPropertyFileSnitch. Just need to assess what the impact is to a running-active cluster restarting 1 node at a time. Given that I'm using Simple Strategy initially, I'm guessing there will be no impact. With regards to the non-ap

Re: Cassandra data migration from 1.9.8 to 2.0.2

Thanks Robert. I wrongly mentioned the source Cassandra version. Actual source version is 1.2.9. Regards, LakshmiKanth On Tue, Mar 18, 2014 at 12:06 PM, Robert Coli wrote: > On Mon, Mar 17, 2014 at 6:19 PM, Lakshmi Kanth wrote: > >> Cassandra 1.9.8 >> > > No? This version does not exist. >

Re: How to extract information from commit log?

Hi Jonathan, Thank you for the timely reply. I am doing this experiment on a continuous basis. To be more specific, I will issue a large amount of read and write operations to a particular key in a short time interval. I'd like to know the order that write operations happens at each replica.

Re: Cassandra data migration from 1.9.8 to 2.0.2

On Mon, Mar 17, 2014 at 6:19 PM, Lakshmi Kanth wrote: > Cassandra 1.9.8 > No? This version does not exist. > Cassandra 2.0.2 > Cassandra 2.0.x versions up to and including 2.0.5 have serious issues. Including this one, which randomly tombstones your data when you use SSTableloader. https://i

Re: How to extract information from commit log?

Hello, Is this a one time investigative item or are you looking to set something up to do this continuously? Don't recommend trying to read the commit log. You can always use the WRITETIME function in CQL or look within SSTables via the SStable2Json utility to see write times for particular

Re: Cassandra blob storage

On Tue, Mar 18, 2014 at 10:41 AM, prem yadav wrote: > I have been spending some time looking into whether large files(>100mb) > can be stores in Cassandra. As per Cassandra faq: > https://code.google.com/p/mogilefs/ Cassandra is not optimized for single values of this size. Leaving aside Thrift

Re: Cassandra blob storage

On Tue, Mar 18, 2014 at 10:41 AM, prem yadav wrote: > I have been spending some time looking into whether large files(>100mb) > can be stores in Cassandra. As per Cassandra faq: > https://code.google.com/p/mogilefs/ Cassandra is not optimized for single values of this size. Leaving aside Thrift

Re: Cassandra blob storage

@Mohit Bit confused with your reply. For what use cases you find Cassandra useful then? -Vivek On Tue, Mar 18, 2014 at 11:41 PM, Mohit Anchlia wrote: > For large volume big data scenarios we don't recommend using Cassandra as > a blob storage simply because of intensive IO involved during compa

How to extract information from commit log?

Hi Cassandra hackers! I have a question regarding extracting useful information from commit log. Since its a binary log, how should I extract information such as timestamp, values from it? Does anyone know any binary log reader that I can use directly to read commit log? If there is no such

Re: Cassandra blob storage

For large volume big data scenarios we don't recommend using Cassandra as a blob storage simply because of intensive IO involved during compation, repair etc. Cassandra store is only well suited for metadata type storage. However, if you are fairly low volume then it's a different story, but if you

Re: Cassandra blob storage

Thanks Brian, I have seen that. Its more of a workaround and a hack. Of course a great solution. But my question is more about why Cassandra itself can't support that. Give then Thrift supports frames. Thanks. On Tue, Mar 18, 2014 at 5:55 PM, Brian O'Neill wrote: > You may want to look at: > ht

Re: Cassandra blob storage

You may want to look at: https://github.com/Netflix/astyanax/wiki/Chunked-Object-Store -brian --- Brian O'Neill Chief Technology Officer Health Market Science The Science of Better Results 2700 Horizon Drive € King of Prussia, PA € 19406 M: 215.588.6024 € @boneill42

Cassandra blob storage

Hi, I have been spending some time looking into whether large files(>100mb) can be stores in Cassandra. As per Cassandra faq: *"Currently Cassandra isn't optimized specifically for large file or BLOB storage. However, files of around 64Mb and smaller can be easily stored in the database without s

Re: Relation between Atomic Batches and Consistency Level

Alright, this is much better. The main thing I’m trying to figure out is that if there is a way to stop the batch if the first statement fails or there is a better pattern/construct for Cassandra to handle that scenario. - Drew On Mar 18, 2014, at 4:46 AM, Jonathan Lacefield wrote: > Okay you

Re: Problems with adding datacenter and schema version disagreement

Oh, one more question: what should be configuration for storing system_traces keyspace? Should it be replicated or stored locally? Regards Olek 2014-03-18 16:47 GMT+01:00 olek.stas...@gmail.com : > Ok, i've dropped all system keyspaces, rebuild cluster and recover > schema, now everything looks ok

Re: Problems with adding datacenter and schema version disagreement

Ok, i've dropped all system keyspaces, rebuild cluster and recover schema, now everything looks ok. But main goal of operations was to add new datacenter to cluster. After starting node in new cluster two schema versions appear, one version is held by 6 nodes of first datacenter, second one is in n

Re: Relation between Atomic Batches and Consistency Level

Okay your question is clear to me know. My understanding, after talking this through with some of the engineers here, is that we have 2 levels of success with batches: 1) Did the batch make it to the batch log table? [yes or no] - yes = success - no = not success 2) Did each sta

Re: Cassandra DSC 2.0.5 not starting - "* could not access pidfile for Cassandra"

For others who get stuck with this in future, here is fix that worked for me: http://askubuntu.com/questions/435749/cant-start-an-application-as-service-but-running-as-standalone-process-simply On Tue, Mar 11, 2014 at 9:24 PM, Michael Shuler wrote: > On 03/11/2014 08:47 AM, Ken Hancock wrote: >

Re: Cassandra (2.0.4) pagination and total records?

With Cassandra 2.0.x and Java driver 2.0.0 you can set the fetch size on the query and then use Resulset.iterator(). It will iterate over your data set by loading batches of size = fetch size Le 18 mars 2014 01:39, "Philip G" a écrit : > Thanks for the links. > > As I'm messing around with CQL, I