Re: Session timeout

I've been in this community and mailing list quite a while now and it's hard to find questions without answer. There are lots of good experts willing to help here. If you don't see you question answered I'd advice you to send it again, because its also true that the mailing list has quite a lot of

Re: missing rows while importing data using sstable loader

Hi Romain, The RF was set to 2. I changed it to one. CREATE KEYSPACE mordor WITH replication = {'class' : 'SimpleStrategy', 'replication_factor' : 1} AND durable_writes = true; re-inserted the columns, still missing rows. Regards, Arindam On 29 January 2016 at 15:14, Romain Hardouin

Re: compaction throughput

Keep in mind that compaction in LCS can only run 1 compaction per level. Even if it wants to run more compactions in L0 it might be blocked because it is already running a compaction in L0. BR Jan On 01/16/2016 01:26 AM, Sebastian Estevez wrote: LCS is IO ontensive but CPU is also relevant.

Re: Session timeout

Carlos, I went through Java and Python drivers... didn't find anything like that. Can you bring me example from your Ruby driver? Let me also make sure we are on the same page - I'm talking about session timeout due to inactivity, not read timeout or something like that. Thanks, Oleg On Fri,

Re: missing rows while importing data using sstable loader

Hi, I assume a RF > 1. Right?What is the consistency level you used? cqlsh use ONE by default. Try: cqlsh> CONSISTENCY ALLAnd run your query again. Best,Romain Le Vendredi 29 janvier 2016 13h45, Arindam Choudhury a écrit : Hi Kai, The table schema is:

Re: Session timeout

Not a problem, Carlos, at least you tried :) I have overall a big problem with my queries to Cassandra community. Most of them are not getting answered. Oleg On Fri, Jan 29, 2016 at 8:03 AM, Carlos Alonso wrote: > Oh, I thought you meant read/write timeout, not session

Re: missing rows while importing data using sstable loader

I will check the output of nodetool cfstats. Its from version 2.1.2 to version 2.1.9. On 29 January 2016 at 16:02, Jack Krupansky wrote: > Are these sstables from an existing Cassandra cluster or generated by a > program? > > If the former, do a nodetool tablestats or

Re: Session timeout

Oh, I thought you meant read/write timeout, not session timeout due to inactivity... Not sure there's such option. Sorry Carlos Alonso | Software Engineer | @calonso On 29 January 2016 at 13:35, oleg yusim wrote: > Carlos, > > I went through

Re: missing rows while importing data using sstable loader

Are these sstables from an existing Cassandra cluster or generated by a program? If the former, do a nodetool tablestats or cfstats to get the sstable count and compare it to both the number of sstables that the loader is reading from and the number that end up in the target cluster. What

Re: missing rows while importing data using sstable loader

I am counting the rows with "select count(*) from mordor.things_values_meta;" I am doing one node cluster to one node cluster for testing. On 29 January 2016 at 16:20, Jack Krupansky wrote: > And how are you counting the rows? With a query? If, so, what is the >

Re: Cassandra's log is full of mesages reset by peers even without traffic

Hi Jean, Please make sure that your Firewall is not dropping TCP connections which are in use. Tcp keep alive on all nodes must be less than the firewall setting. Please refer to  https://docs.datastax.com/en/cassandra/2.0/cassandra/troubleshooting/trblshootIdleFirewall.html  for details on TCP

Re: Session timeout

Hi Carlos, Thanks for your anwer. Can you, please, get me a bit me information? What is the driver? JDBC? What is the name of configuration file? Thanks, Oleg On Fri, Jan 29, 2016 at 5:12 AM, Carlos Alonso wrote: > Hi Oleg. > > The drivers have builtin the timeout

Re: Session timeout

I personally don't use the Java but the Ruby driver, but I'm pretty sure you'll be able to find it in the docs: https://github.com/datastax/java-driver Carlos Alonso | Software Engineer | @calonso On 29 January 2016 at 13:15, oleg yusim wrote:

Re: Session timeout

Hi Oleg. The drivers have builtin the timeout configurable functionality. Hope it helps. Carlos Alonso | Software Engineer | @calonso On 28 January 2016 at 22:18, oleg yusim wrote: > Greetings, > > Does Cassandra support session timeout? If

Re: missing rows while importing data using sstable loader

Arindam, what's the table schema and what does your query to retrieve the rows look like? On Fri, Jan 29, 2016 at 7:33 AM, Arindam Choudhury < arindam.choudh...@ackstorm.com> wrote: > Hi, > > I am importing data to a new cassandra cluster using sstableloader. The > sstableloader runs without

Re: missing rows while importing data using sstable loader

Hi Kai, The table schema is: CREATE TABLE mordor.things_values_meta ( thing_id text, key text, bucket_timestamp timestamp, total_rows counter, PRIMARY KEY ((thing_id, key), bucket_timestamp) ) WITH CLUSTERING ORDER BY (bucket_timestamp ASC) AND bloom_filter_fp_chance =

missing rows while importing data using sstable loader

Hi, I am importing data to a new cassandra cluster using sstableloader. The sstableloader runs without any warning or error. But I am missing around 1000 rows. Any feedback will be highly appreciated. Kind Regards, Arindam Choudhury

Re: Cassandra's log is full of mesages reset by peers even without traffic

Hi anuj, Thx for your replay, acctually I paste part of the result of the command gre done over one log and I can see only the ip of the machine local grep "Unexpected exception during request" /var/opt/hosting/log/cassandra/system.log INFO [SharedPool-Worker-1] 2016-01-29 10:40:47,744

Cassandra's log is full of mesages reset by peers even without traffic

Hello guys, I have a cluster cassandra 2.1.12 with 6 nodes. All the logs of my nodes are having this messages marked as INFO INFO [SharedPool-Worker-1] 2016-01-29 10:40:57,745 Message.java:532 - Unexpected exception during request; channel = [id: 0xff15eb8c, / 172.16.162.4:9042]

Re: Session timeout

Hi Carlos, Thanks for encouraging me, I kind of grew a bit desperate. I'm security person, not a Cassandra expert, and doing security assessment of Cassandra DB, I have to rely on community heavily. I will put together a composed version of all my previous queries, will title it "Security

Re: Session timeout

I think the reason why most of your queries aren't being answered is because you're asking questions that most people don't have the answer to. On the automatic disconnect, anyone using Cassandra in prod doesn't really need to think about it because we're always running queries, perhaps millions a

Re: missing rows while importing data using sstable loader

Why in cqlsh when I query "select count(*) from mordor.things_values_meta ;" it says: 4692 But in nodetool cfstats it says Number of keys (estimate): 4720? On 29 January 2016 at 16:25, Arindam Choudhury < arindam.choudh...@ackstorm.com> wrote: > I am counting the rows with "select count(*) from

Re: Security labels

Jack, Thanks for your suggestion. I'm familiar with Cassandra documentation, and I'm aware of differences between DSE and Cassandra. Questions I ask here are those, I found no mention about in documentation. Let's take security labels for instance. Cassandra documentation is completely silent on

Security labels

Hi Oleg, I understand your frustration but unfortunately, in the terms of your security assessment, you have fallen into a mismatch for Cassandra's utility. The eventuality of having multiple sockets open without the query input for long durations of time isn't something that was

Re: missing rows while importing data using sstable loader

I agree that there should be more clear doc on exactly how the estimation is calculated. When I inquired about this recently the response was that it should be within about 2% of the actual key count. I started looking at the code, but I ran out of time before I chased down all the subsidiary

Re: missing rows while importing data using sstable loader

And how are you counting the rows? With a query? If, so, what is the query. Using nodetool cfstats (estimated) key count? Or... what? Are the tokens for the missing rows is the same range and a distinct range from the rest of the data in the original cluster? How many nodes in the original

Re: Security labels

To answer any future questions along these same lines, I suggest that you start by simply searching the doc and search the github repo for the source code for the relevant keywords. That will give you the definitive answers quickly. If something is missing, feel free to propose that it be added

Tuning chunk_length_kb in cassandra 2.1.12

Hi guys I want to set the param chunk_length_kb in order to improve the read latency of my cassandra_stress's test. This is the table CREATE TABLE "Keyspace1".standard1 ( key blob PRIMARY KEY, "C0" blob, "C1" blob, "C2" blob, "C3" blob, "C4" blob ) WITH

Re: Session timeout

Jon, I suspected something like that. I did a bit of learning on Cassandra before starting my assessment, and I understand that you are right, and it is generally not used like that. However (taking off my developer hat and putting on my security architect hat), from the security point of view

Re: Security labels

Dani, I really appreciate you response. Actually, session timeouts and security labels are two different topics (first is about attack when somebody opened, say, ssh window to DB, left his machine unattended and somebody else stole his session, second - to enable DB to support what called MAC

Re: Security labels

Also -- it looks like you're really asking questions about session timeouts and security labels as they associate, would be more helpful to keep in one thread. :) On Friday, January 29, 2016, Dani Traphagen wrote: > Hi Oleg, > > I understand your frustration but

Re: Questions about the replicas selection and remote coordinator

Hi Jun, The 2 diagrams you are comparing come from versions of Cassandra that are significantly different - 1.2 in the first case and 2.1 in the second case, so it's not surprising that there are differences. since you haven't qualified your question with the Cassandra version you are asking

RE: Questions about the replicas selection and remote coordinator

Hi Steve, Thank you so much for your reply. Yes, you're right, I'm using the version of 2.1. So based on this, I think I'm outdated. However, this comes to another interesting question: why we change this part from version 1 to version 2. As we can see that in version 1, there's

Questions about the replicas selection and remote coordinator

Hi there, I have some questions about the replicas selection. Let's say that we have 2 data centers: DC1 and DC2, the figure also be got from link here: https://docs.datastax.com/en/cassandra/1.2/cassandra/images/write_access_multidc_12.png. There're 10 nodes in each data center. We

Cassandra driver class

I'm just getting started with Cassandra, and am trying to integrate it with JBoss. I'm configuring the standalone-ha-full.xml file, but don't know what to use for the driver class. For example, I have this: com.datastax.driver.core. What do I replace ""

Re: Session timeout

> For instance, way AAA (authentication, authorization, audit) is done, doesn't > allow for centralized account and access control management, which in reality > translates into shared accounts and no hierarchy. Authentication and Authorization are both pluggable. Any organization can write

Re: Cassandra driver class

>From the little reading I did do about TEIID it sounded as if they do have a connector that uses the Cassandra Java Driver, which is of course a good thing. But that doesn't make their connector itself a topic for the Java Driver list. I mean, the folks on the Java List are no more likely to know

Re: Session timeout

To throw my (unsolicited) 2 cents into the ring, Oleg, you work for a well-funded and fairly large company. You are certainly free to continue using the list and asking for community support (I am definitely not in any position to tell you otherwise, anyway), but that community support is by

Re: EC2 storage options for C*

Bryan, Correct, I should have clarified that. I'm evaluating instance types based on one SSD or two in RAID 0. I thinking its going to be two in RAID 0, but as I've had no experience running a production C* cluster in EC2, I wanted to reach out to the list. Sorry for the half-baked question :)

Re: Slow performance after upgrading from 2.0.9 to 2.1.11

@JC, Get the pid of your target java process (something like "ps -ef | grep -i cassandra") . Then do a kill -3 (at unix/linux) Check the stdout logfile of the process. it should contain the threaddump. If you found it, then great! Let that kill -3 loop for about 2 or 3 minutes. Herafter copy

Re: Session timeout

No offense, but my suggestion here is that you write up a preliminary list of your own answers based on your own reading of the doc, specs, and white papers (and source code) and post that list, like on Google Docs, for people to review in bulk, rather than force all Cassandra users on this list

Re: Session timeout

Jack, I have to note, Cassandra documentation the way it stays now, is not nearly detailed enough. For instance: https://docs.datastax.com/en/cassandra/2.1/cassandra/configuration/configLoggingLevels_r.html is all Cassandra has to say about logging. The reason why I bring my questions to the

Re: Session timeout

On Fri, Jan 29, 2016 at 3:12 PM, Jack Krupansky wrote: > One last time, I'll simply renew my objection to the way you are abusing > this list. > FWIW, while I appreciate that OP (Oleg) is attempting to do a service for the community, I agree that the flood of single

Re: EC2 storage options for C*

RAID 0 regardless of instance type* On Friday, January 29, 2016, Eric Plowe wrote: > Bryan, > > Correct, I should have clarified that. I'm evaluating instance types based > on one SSD or two in RAID 0. I thinking its going to be two in RAID 0, > but as I've had no

Re: Security labels

Thanks Dani! Oleg On Fri, Jan 29, 2016 at 3:28 PM, Dani Traphagen wrote: > ​Hi Oleg, > > Thanks that helped clear things up! This sounds like a daunting task. I > wish you all the best with it. > > Cheers, > Dani​ > > On Fri, Jan 29, 2016 at 10:03 AM, oleg yusim

EC2 storage options for C*

My company is planning on rolling out a C* cluster in EC2. We are thinking about going with ephemeral SSDs. The question is this: Should we put two in RAID 0 or just go with one? We currently run a cluster in our data center with 2 250gig Samsung 850 EVO's in RAID 0 and we are happy with the

Re: EC2 storage options for C*

Do you have any idea what kind of disk performance you need? Cassandra with RAID 0 is a fairly common configuration (Al's awesome tuning guide has a blurb on it https://tobert.github.io/pages/als-cassandra-21-tuning-guide.html), so if you feel comfortable with the operational overhead it seems

Re: Session timeout

Jack, Appreciate the links. As I mentioned, I looked over both DSE and Cassandra sets of documentation, and ran some experiments on my Cassandra installation. What I'm bringing here is something I couldn't find definitive answer for in any of the above-mentioned sources. For instance, regarding

Re: Cassandra driver class

Fully correct Steve, it is a source of confusion an having a standard pool at app/driver level will work as good as the jee solution, but just like the cql foresees an easy developer entry for cassandra because it is similar to sql, the jee datasource could do the same in front of the middleware

Re: EC2 storage options for C*

If you have to ask that question, I strongly recommend m4 or c4 instances with GP2 EBS. When you don’t care about replacing a node because of an instance failure, go with i2+ephemerals. Until then, GP2 EBS is capable of amazing things, and greatly simplifies life. We gave a talk on this topic

Problem while migrating a single node cluster from 2.1 to 3.2

Hi, I am a newbie when it comes to Cassandra administration and operation. We have a single node cluster running 2.1 in EC2 and we are planning to move it to better single machine instance and want to run 3.2 on that. I installed 3.2 on the new machine and created a snapshot of the old cluster

Re: Slow performance after upgrading from 2.0.9 to 2.1.11

I am having the same issue after upgrade cassandra 2.1.12 from 2.0.10. I am not good on jvm so I would like to know how to do what @CorryOpdenakker propose with cassandra. :) I check concurrent_compactors Saludos Jean Carlo "The best way to predict the future is to invent it" Alan Kay On

Re: Session timeout

One last time, I'll simply renew my objection to the way you are abusing this list. You'll hear no further reply from me and I will begin marking any more of your excessive inquiries as spam. If others in the community wish to do your security review for you one item at a time, that is their

Re: Security labels

​Hi Oleg, Thanks that helped clear things up! This sounds like a daunting task. I wish you all the best with it. Cheers, Dani​ On Fri, Jan 29, 2016 at 10:03 AM, oleg yusim wrote: > Dani, > > I really appreciate you response. Actually, session timeouts and security >

Re: Cassandra driver class

It's probably a source of some confusion that in the JEE world, the driver isn't pooled, but the data source is. Since the Java Driver for Cassandra includes the pooling, there's no need for a JEE data source on top of it. This also means that the Java Driver for Cassandra isn't a one-for-one

Re: Session timeout

There is some more detail on DSE Security in this white paper: http://www.datastax.com/wp-content/uploads/2014/04/WP-DataStax-Enterprise-SOX-Compliance.pdf It mentions auditing, for example. I think you were asking abut that earlier. There may be some additional info or discussion related to

Re: Session timeout

Jeff, Understood. Thanks for your response. I would put together my questions in one thread here, will title it "Security". Then I will move whatever was not answered to the dev thread. Thanks, Oleg On Fri, Jan 29, 2016 at 11:42 AM, Jeff Jirsa wrote: > > > For

Re: why one of the new added nodes' bootstrap is very slow?

Hi Dillon > What should I do for this wrong bootstrap? You should first remove the .184 nodes (the node with almost no data). The standard command is *nodetool decommission* from the node you want remove from the cluster. Yet this would move the data from the node we want to remove to other

Re: Questions about the replicas selection and remote coordinator

Hi Jun, The replicas are chosen according to factors that are generally more easily selected internally, as is the case with coordinators. Even if the replicas were selected in a completely round-robin fashion initially, they could end up being re-distributed as a result of node failures,

Re: Session timeout

On Fri, Jan 29, 2016 at 8:17 AM, oleg yusim wrote: > Thanks for encouraging me, I kind of grew a bit desperate. I'm security > person, not a Cassandra expert, and doing security assessment of Cassandra > DB, I have to rely on community heavily. I will put together a composed

Re: Slow performance after upgrading from 2.0.9 to 2.1.11

Hello, We have another update on performance on 2.1.11. compression_chunk_size didn’t really help much but We changed concurrent_compactors from default to 64 in 2.1.11 and read latencies improved significantly. However, 2.1.11 read latencies are still 1.5 slower than 2.0.9. One thing we

Re: Slow performance after upgrading from 2.0.9 to 2.1.11

On Fri, Jan 29, 2016 at 12:30 PM, Peddi, Praveen wrote: > > Hello, > We have another update on performance on 2.1.11. compression_chunk_size didn’t really help much but We changed concurrent_compactors from default to 64 in 2.1.11 and read latencies improved significantly.

Re: Cassandra driver class

I think both of those options expect a JDBC driver, while the DataStax Java driver is not one. As a side note, if you'd provide a more detailed description of the setup you want to get and post it to the Java driver mailing list

Re: Slow performance after upgrading from 2.0.9 to 2.1.11

Hi guys, Cassandra is still new for me, but I have a lot of java tuning experience. For root cause detection of performance degradations its always good to start with collecting a series of java thread dumps. Take at problem occurrence using a loopscript for example 60 thread dumps with an

Re: Slow performance after upgrading from 2.0.9 to 2.1.11

Thanks Nate for your quick reply. We will test with different concurrent_compactors settings. It would save lot of time for others if documentation can be fixed. We spent days to come up with this setting and that too by chance. As far as data folder and IO is concerned. I confirmed that data

Re: Session timeout

Alex, No offense are taken, your question is absolutely legit. As we used to joke in security world "putting on my black hat"/"putting on my white hat" - i.e. same set of questions I would be asking for hacking and protecting the product. So, I commend you for being careful here. Now, at that

Re: Cassandra driver class

What about this cassandra specific howto explained in a recent jboss doc? https://docs.jboss.org/author/display/TEIID/Cassandra+Data+Sources?_sscc=t Im also searching for the real recommended way of connecting to a cassandra db from a jee server, but I didnt found any standard documented solution

Re: Cassandra driver class

Unfortunately, somebody is likely going to need to educate us in the Cassandra community as to what a JBOSS VDB and TEIID really are. For now, our response will probably end up being that you should use the Java Driver for Cassandra, bypassing any JBOSS/VDB/TEIID support, for now. That TEIID link