Rack Awareness

I am getting ready to start what I understand as a rack aware repair. This is to run the repair on each node within the rack resulting in a repair of the entire cluster. My question comes due to a highly out of balance set of racks and I want to know if Cassandra 2.1.12 is smart enough to

Re: Rack Awareness

What command exactly do you think gives you a rack-aware repair? On Tue, Aug 29, 2017 at 11:52 AM, Mark Furlong wrote: > I am getting ready to start what I understand as a rack aware repair. This > is to run the repair on each node within the rack resulting in a repair

C++ driver - CassCluster lifetime

Hey all, Working with the datastax C++ driver right now, and I'm wondering, is there a strong need for me to retain a valid CassCluster object after my session has been connected? Is the cost of a CassCluster creation minimal, such that later calls to create/connect a session I could just create

Re: Running nodetool gossipinfo

Each of those fields is a versioned application state (except generation and heartbeat). The version applies to the application state, it's different than the Cassandra version. Each line (DC, RACK, RELEASE_VERSION, etc) will be: Name:Version:Value If you see 2.1.11 and version 7, then the

RE: Running nodetool gossipinfo

Not sure I follow the version of Cassandra is 2.1.11 correct? And 7 is the version number of Cassandra that is running locally. I don’t quite follow, if you have time could you clarify? Thanks From: Xiaolong Jiang [mailto:xiaolong...@gmail.com] Sent: Tuesday, August 29, 2017 3:35 PM To:

Running nodetool gossipinfo

Hello, Running nodetool gossipinfo trying to find out in the result set for release version , what does the first digit (7) represent? I assume the rest is the actual version number. RELEASE_VERSION:7:2.1.11 Thanks Paul This email (including any attachments) is proprietary to Aspect Software,

Re: Running nodetool gossipinfo

7 is the version number locally in each instance representing the instance state used by gossiper. it will increase at least one every second Sent from my iPhone > On Aug 29, 2017, at 11:40 AM, Harper, Paul wrote: > > Hello, > Running nodetool gossipinfo trying to find

Re: why the cluster does not work well after addding two new nodes

Hi , What happened wrong from starting, I am just listing down:- 1) Had 2 nodes servers but created Keyspace with RF 3. [Always make sure RF <= Total No. of Nodes] 2) While Adding New Nodes, Make sure that Auto_bootstraping is Enable or not. 3) Once You added 2 new nodes, better things will be you

why the cluster does not work well after addding two new nodes

Hi, I have a cluster with two node servers（I know it’s in a wrong way but it‘s builded by another colleague who has left）， and it's keyspace set like： CREATE KEYSPACE my_keyspace WITH replication = {'class': 'SimpleStrategy', 'replication_factor': '3'} AND durable_writes = true; one day my

Re: Rack Awareness

Cassandra understands racks based on the configured snitch and the rack assigned to each node (for example in cassandra-rackdc.properties if using GossipingPropertyFileSnitch). If you have racks configured, to perform a "rack-aware" repair you would simply need to run repair on only one rack. Note

Re: Working With Prepared Statements

>From memory prepared statements that are idempotent will not be set as idempotent, so if you are using prepared statements that you know are idempotent you should make sure to set idempotent on them. For java driver see https://github.com/datastax/java-driver/tree/3.x/manual/idempotence​

Re: Conection refuse

Hi Lucas, Thanks for your response. So I checked the system.log and I found the following error at the end which I think is causing the problem. Fatal exception during initialization org.apache.cassandra.exceptions.ConfigurationException: Found system keyspace files, but they couldn't be loaded!

Re: UnauthorizedException: user has no select permissions when quering Cassandra

We have that keyspace replicated to the same number of nodes in the ring. Right now I can’t even run select * from system_auth.users without it timeing out. From: Akhil Mehra Reply-To: "user@cassandra.apache.org" Date: Tuesday, August 29, 2017

RE: Running nodetool gossipinfo

Thank You Jeff. From: Jeff Jirsa [mailto:jji...@gmail.com] Sent: Tuesday, August 29, 2017 3:59 PM To: cassandra Subject: Re: Running nodetool gossipinfo Each of those fields is a versioned application state (except generation and heartbeat). The version applies to

Re: UnauthorizedException: user has no select permissions when quering Cassandra

I could be that authorisation is added to a node without increasing the replication factor for the system_auth keyspace (https://docs.datastax.com/en/cassandra/3.0/cassandra/configuration/secureConfigInternalAuth.html

Re: UnauthorizedException: user has no select permissions when quering Cassandra

Yes. We’ve tried them all. From: Akhil Mehra Reply-To: "user@cassandra.apache.org" Date: Tuesday, August 29, 2017 at 4:06 PM To: "user@cassandra.apache.org" Subject: Re: UnauthorizedException: user has no select

Re: Working With Prepared Statements

Insights, anyone? Shalom Sagges DBA We Create Meaningful Connections On Mon, Aug 28, 2017 at 10:43 AM, Shalom Sagges wrote: > Hi Everyone, > > I want to

Re: UnauthorizedException: user has no select permissions when quering Cassandra

Double check the replication config for that keyspace, make sure all data centers are spelled properly and there is no extra white space -- Jeff Jirsa > On Aug 29, 2017, at 2:49 PM, Chuck Reynolds wrote: > > > We have that keyspace replicated to the same number of

nodetool gossipinfo question

Hi – I have a question on the significance a particular attribute in the output result for ‘nodetool gossipinfo’: RELEASE_VERSION. We have a node that is periodically crashing with nothing really of significance in the logs and we’re trying to ascertain if it’s an OS issue or something to do

Re: Conection refuse

Akhil, Commit log directory from yaml file is: /var/lib/cassandra/commitlog So basically I removed it. Can I copy a new one from another node? or somehow generate one? Yes, the rm -rf was on the original and the only node. I stopped the C* and ran the rm -rf /var/lib/cassandra/*. At this point,

Re: Working With Prepared Statements

Do you have any concrete questions re prepared statements? They are faster to execute since the statement is already parsed and in C* and you just pass the parameters. No additional statement processing is needed. Matija On Tue, Aug 29, 2017 at 12:33 PM, Shalom Sagges

Re: Working With Prepared Statements

I don't see any disadvantages or warning signs. You will see a performance increase on moderate request rate frequency. On Tue, Aug 29, 2017 at 1:28 PM, Shalom Sagges wrote: > Hi Matija, > > I just wish to know if there are any disadvantages when using prepared >

Re: Working With Prepared Statements

Sounds great then. Thanks a lot guys!  Shalom Sagges DBA We Create Meaningful Connections On Tue, Aug 29, 2017 at 2:41 PM, Nicolas Guyomar wrote: >

Re: Conection refuse

Hello Amir, You should see the log. If it was installed by the apt-get tool, it should be in /var/log/cassandra/system.log. It can occur when the schema of the node you are trying to connect is out of date with the cluster. How many nodes are there in you cluster? What is the output of "nodetool

Re: Working With Prepared Statements

Hi Matija, I just wish to know if there are any disadvantages when using prepared statement or any warning signs I should look for. Queries will run multiple times so it fits the use case. Thanks! Shalom Sagges DBA

Re: Working With Prepared Statements

Hi Shalom, AFAIK, you are completely safe with prepared statement, there are no caveats using them, and you will have better performance. Make sure to only prepare them once ;) On 29 August 2017 at 13:41, Matija Gobec wrote: > I don't see any disadvantages or warning

Re: Working With Prepared Statements

I would suggest to read this post by the last pickle: http://thelastpickle.com/blog/2016/09/15/Null-bindings-on-prepared-statements-and-undesired-tombstone-creation.html and make sure you are not concerned by the mentioned behavior, because some people still choose to use C* v2.X because of some

Re: Working With Prepared Statements

Thanks a lot! I'll make sure it'll be prepared once. Shalom Sagges DBA T: +972-74-700-4035 We Create Meaningful Connections On Tue, Aug

Re: Working With Prepared Statements

That's a good to know post. Thanks for the info Nicolas! Shalom Sagges DBA T: +972-74-700-4035 We Create Meaningful Connections On

Re: Working With Prepared Statements

Hi Shalom, If that helps.. From the documentation : "You should prepare only once, and cache the PreparedStatement in your application (it is thread-safe). If you call prepare multiple times with the same query string, the driver will log a warning” On August 29, 2017 at 12:04:34 PM, Shalom

Re: Conection refuse

If the data is not important then stop all nodes. On each node empty your commitlog, data, hints and saved_cache directories. Start one node. Wait for it to boot up successfully i.e. logs have no errors and you can connect to it using cqlsh. Start your second node and make sure it bootstraps

Re: Conection refuse

To install make sure: Your cluster name on each node are the same. You configure your seed nodes. Make one node the seed node and added seed configuration to all your yaml files. Ensure that intra-node communication is on the same port. By default this is on port 7000 Do not startup all nodes

Re: Conection refuse

Thanks Akhil, I will follow your steps. Thanks for the links. Best, Amirali On Tue, Aug 29, 2017 at 8:19 PM, Akhil Mehra wrote: > To install make sure: > > Your cluster name on each node are the same. > You configure your seed nodes. Make one node the seed node and added

Re: Conection refuse

What directory was the data and commit logs stored on the original working node. You can look up your cassandra.yaml to figure this out. Its good to confirm. Was the rm -rf run on the original working node? Cheers, Akhil > On 30/08/2017, at 9:37 AM, Amir Shahinpour

Re: UnauthorizedException: user has no select permissions when quering Cassandra

What consistency are you running the query with? Does the query timeout even with a consistency of one? > On 30/08/2017, at 9:49 AM, Chuck Reynolds wrote: > > > We have that keyspace replicated to the same number of nodes in the ring. > > Right now I can’t even run

UnauthorizedException: user has no select permissions when quering Cassandra

I’m receiving the following error when quering a table that I know the user has super user rights to. It only happens about 10% of the time. com.datastax.driver.core.exceptions.UnauthorizedException: User test has no SELECT permission on or any of its parents.

Re: Conection refuse

Cassandra is doing a health check when it is starting up and failing due to being unable to ready files in the system key space. Here is the comment in the segment of the code that threw the exception.

Re: Conection refuse

Yes both of the nodes are down. On Aug 29, 2017 2:30 PM, "Akhil Mehra" wrote: > Cassandra is doing a health check when it is starting up and failing due > to being unable to ready files in the system key space. Here is the comment > in the segment of the code that threw

Re: Conection refuse

Thanks Akhil, I will do it. For setting up my second node, do you have any good source that I can follow to make sure I am doing everything correct? I have been googling around and quite frankly all the source that I found in the Google were kind of different from each other and I guess that is

Re: timeouts on counter tables

Is it possible at all that you may have a data hotspot if it's not hardware-related? On Mon, Aug 28, 2017 at 11:30 AM, kurt greaves wrote: > If every node is a replica it sounds like you've got hardware issues. Have > you compared iostat to the "normal" nodes? I assume