Re: [E] Re: Cassandra tarball install and systemd

[Saha, Sushanta K]

Thanks Aaron! Appreciate it.

 Sushanta


On Wed, Feb 9, 2022 at 11:13 AM Aaron Ploetz  wrote:

> > I am starting Cassandra with $CASSANDRA_HOME/bin/cassandra
>
> When starting Cassandra, it accepts a PID file location with the -p flag:
>
> $CASSANDRA_HOME/bin/cassandra -p /var/run/cassandra/cassandra.pid
>
> Start Cassandra with that, and then the PID file will be there.  Assuming
> of course, that the user starting Cassandra has access to
> /var/run/casandra/.
>
> Aaron
>
>
> On Wed, Feb 9, 2022 at 9:53 AM Bowen Song  wrote:
>
>> Isn't the /etc/init.d/cassandra script supposed to create the PID file if
>> it doesn't exist? See:
>> https://github.com/apache/cassandra/blob/cb1c8f9d34edfa639096d2d122dfd0ee6d23b479/debian/init#L83
>> <https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_apache_cassandra_blob_cb1c8f9d34edfa639096d2d122dfd0ee6d23b479_debian_init-23L83=DwMFaQ=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ=JaNakyvP8b5eGvWhmxll6L4SNrrqHGq3Ghe3-Mb4Nezhm-3SiJqFhK3ICb6tsog4=Cumb-omCSWDH8xr3ojkkGHKYMfrnF4CVVpwI2S4_RP-M0ZK-hxYM0Nj3UzAEByHY=NpZtlTSFesYBpaKSb44q7Elhw9MoPEpnNH5oPqjfOgA=>
>>
>>
>> On 09/02/2022 15:17, Saha, Sushanta K wrote:
>>
>> I picked up the script */etc/init.d/cassandra* from the net. Not sure if
>> tarball installation includes such a script. It should.
>>
>> This script is using the following line:
>> *pid_file=/var/run/cassandra/cassandra.pid*
>>
>> But, there is no such *.pid* file that I can find. I am starting
>> Cassandra with $CASSANDRA_HOME/bin/cassandra.
>>
>> Appreciate any pointer for this auto stop and start of Cassandra.
>>
>> Thanks & Regards
>>  Sushanta
>>
>> --
>>
>> *Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
>> * VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
>> 949-286-8810*
>>
>>

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

Cassandra tarball install and systemd

[Saha, Sushanta K]

I picked up the script */etc/init.d/cassandra* from the net. Not sure if
tarball installation includes such a script. It should.

This script is using the following line:
*pid_file=/var/run/cassandra/cassandra.pid*

But, there is no such *.pid* file that I can find. I am starting Cassandra
with $CASSANDRA_HOME/bin/cassandra.

Appreciate any pointer for this auto stop and start of Cassandra.

Thanks & Regards
 Sushanta

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

Re: [E] Re: Anyone connecting the Cassandra on a server

[Saha, Sushanta K]

Thanks Bowen!

 Sushanta


On Fri, Nov 19, 2021 at 4:01 PM Bowen Song  wrote:

> This could be two questions with different answers:
>
>
> 1. Is there anyone / who is connected to the Cassandra server right now?
>
> Use the netstat or ss command and check the active TCP connections on
> native port (default is 9042)
>
>
> 2. Is there anyone / who is connecting to the Cassandra servers between
> now and next hour/day/week/month/etc.?
>
> Use iptables/nftables to log new TCP connections (ct state new) on that
> port
>
>
> On 19/11/2021 18:12, Saha, Sushanta K wrote:
>
> I need to shutdown an old Apache Cassandra server for good. Running 3.0.x.
> Any way I can determine if anyone is still connecting to the Cassandra
> instance running on this server?
>
> Thanks
>  Sushanta
>
>

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

Re: [E] Re: Anyone connecting the Cassandra on a server

[Saha, Sushanta K]

Thanks a lot Soumya, Surbhi, and Paul. Appreciate your help!

 Sushanta


On Fri, Nov 19, 2021 at 2:19 PM Paul Chandler  wrote:

> I wrote a blog post describing how to do this a few years ago:
> http://www.redshots.com/who-is-connecting-to-a-cassandra-cluster/
> <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.redshots.com_who-2Dis-2Dconnecting-2Dto-2Da-2Dcassandra-2Dcluster_=DwMFaQ=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ=JaNakyvP8b5eGvWhmxll6L4SNrrqHGq3Ghe3-Mb4Nezhm-3SiJqFhK3ICb6tsog4=v8A8dX7qL7P4J2FfSNDQM8X1fgwnI0CBYjENorSI5AU=M-qeUZejaaOBgcnSk5MMSuk9tMyI6HrTbFYZARlzUmQ=>
>
>
> Sent from my iPhone
>
> On 19 Nov 2021, at 18:13, Saha, Sushanta K <
> sushanta.s...@verizonwireless.com> wrote:
>
> 
> I need to shutdown an old Apache Cassandra server for good. Running 3.0.x.
> Any way I can determine if anyone is still connecting to the Cassandra
> instance running on this server?
>
> Thanks
>  Sushanta
>
>

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

Anyone connecting the Cassandra on a server

[Saha, Sushanta K]

I need to shutdown an old Apache Cassandra server for good. Running 3.0.x.
Any way I can determine if anyone is still connecting to the Cassandra
instance running on this server?

Thanks
 Sushanta

Latest Supported RedHat Linux version for Cassandra 3.11

[Saha, Sushanta K]

I am currently running Open Source Apache Cassandra 3.11.1 on RedHat 7.7.
But, need to upgrade the OS to RedHat to 7.9 or 8.x.

The site
cassandra.apache.org/doc/latest/cassandra/getting_started/installing.html
has listed "CentOS & RedHat Enterprise Linux (RHEL) including 6.6 to 7.7".
FYI.

Question : Can I run Cassandra 3.11.1 on RedHat 7.9 or 8.x?

Thanks
 Sushanta

Re: [E] Re: bug in cluster key push down

[Saha, Sushanta K]

*primary key (partition, clustering1, clustering2)*

So, the partitioning key has three columns. You need to specify values for
all three columns. For clustering columns, you need another parenthesis
like *primary key (partition, (clustering1, clustering2))*

* Sushanta*


On Sun, Jan 12, 2020 at 10:52 AM Jeff Jirsa  wrote:

> Can you open a jira so someone can investigate ? It’s probably just a
> logging / visibility problem, but we should confirm
>
> Sent from my iPhone
>
> On Jan 12, 2020, at 6:04 AM, onmstester onmstester
>  wrote:
>
> 
> Using Apache Cassandra 3.11.2, defined a table like this:
>
>
> *create table my_table(*
>*partition text,*
>*clustering1 int,*
>
> *clustering2 text,*
>
> *data set,*
> *primary key (partition, clustering1, clustering2))*
>
> and configured slow queries threshold to 1ms in yaml to see how queries
> passed to cassandra. Query below:
>
> *select * from my_table where partition='a' and clustering1= 1 and
> clustering2='b'*
>
> would be like this in debug.log of cassandra:
>
> *select * from my_table where partition='a' LIMIT 100>  (it means that the
> two cluster key restriction did not push down to storage engine and the
> whole partition been retrieved)*
>
> but this query:
>
> *select * from my_table where partition='a' and clustering1= 1*
>
> *would be *
>
> *select * from my_table where partition='a' and clustering1= 1 LIMIT 100>
> (single cluster key been pushed down to storage engine)*
>
>
> *So it seems to me that, we could not restrict multiple clustering keys in
> select because it would retrieve the whole partition ?!*
>
> Sent using Zoho Mail
> 
>
>
>
>

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

Adding a datacenter to an existing cluster

[Saha, Sushanta K]

Following:
https://docs.datastax.com/en/cassandra/3.0/cassandra/operations/opsAddDCToCluster.html

Trying to avoid impact on existing DCs. Have 2 questions:

2. Configure the keyspace and create the new datacenter:
 a. Use ALTER KEYSPACE to use the NetworkTopologyStrategy for the following
keyspaces:
◾system: system_distributed and system_traces ===> Currently in
SimpleStrategy.
*Question*: Need to be updated?

6. In the existing datacenters:
 a. On some nodes, update the seeds property in the cassandra.yaml file to
include the seednodes in the new datacenter and restart those nodes.
(Changes to the cassandra.yaml file require restarting to take effect.)
*Question*: Need to restart Cassandra production?

Appreciate the help.

Thanks

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

Pulling in Cassandra metrics in Graphite

[Saha, Sushanta K]

Anyone is aware of a blog/reference/doc that can give me step by step to
accomplish this? Appreciate the help. Thanks in advance!

 Sushanta

Re: [E] Re: nodetool status and node maintenance

[Saha, Sushanta K]

Thanks!

On Mon, Oct 29, 2018 at 10:03 AM Horia Mocioi 
wrote:

> Hello,
>
> Instead of parsing the output from nodetool (running nodetool is quite
> intensive) maybe you could have a java program that would monitor via JMX
> (org.apache.cassandra.net.FailureDetector).
>
> You have less burden compared to running periodically nodetool and more
> control on the things that you could do.
>
> Regards,
> Horia
>
> On fre, 2018-10-26 at 09:15 -0400, Saha, Sushanta K wrote:
>
> I have script that parses "nodetool status" output and emails alerts if
> any node is down. So, when I stop cassandra on a node for maintenance, all
> nodes stats emailing alarms.
>
> Any way to temporarily make the node under maintenance invisible  from
> "nodetool status" output?
>
> Thanks
>
>

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

Re: [E] Re: nodetool status and node maintenance

[Saha, Sushanta K]

Thanks!

On Tue, Oct 30, 2018 at 1:53 AM Max C.  wrote:

> Agree - avoid parsing nodetool, if you can.  I’d add that if anyone out
> there is interested in JMX but doesn’t want to deal with Java, you should
> install Jolokia so you can interact with Cassandra’s JMX data via a
> language independent REST-like interface.
>
> https://jolokia.org/
> <https://urldefense.proofpoint.com/v2/url?u=https-3A__jolokia.org_=DwMFaQ=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ=JaNakyvP8b5eGvWhmxll6L4SNrrqHGq3Ghe3-Mb4Nezhm-3SiJqFhK3ICb6tsog4=iNE5IZ-gs9OYal8kLoQ9E_sQ8AoHOfD2AUyzPjAqv-s=eENoKu4Wvny54Y2hzdeI17CjZp5EIBLLF90445cGNO4=>
>
> Jolokia is what made it possible for us to get out of nodetool parsing and
> into writing tools in our native language — Python.  We’re big fans!
>
> - Max
>
>
> On Oct 29, 2018, at 7:02 am, Horia Mocioi 
> wrote:
>
> Hello,
>
> Instead of parsing the output from nodetool (running nodetool is quite
> intensive) maybe you could have a java program that would monitor via JMX
> (org.apache.cassandra.net.FailureDetector).
>
> You have less burden compared to running periodically nodetool and more
> control on the things that you could do.
>
> Regards,
> Horia
>
> On fre, 2018-10-26 at 09:15 -0400, Saha, Sushanta K wrote:
>
> I have script that parses "nodetool status" output and emails alerts if
> any node is down. So, when I stop cassandra on a node for maintenance, all
> nodes stats emailing alarms.
>
> Any way to temporarily make the node under maintenance invisible  from
> "nodetool status" output?
>
> Thanks
>
>
>

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

Re: [E] Re: nodetool status and node maintenance

[Saha, Sushanta K]

Thanks!

On Fri, Oct 26, 2018 at 2:39 PM Alain RODRIGUEZ  wrote:

> Hello
>
> Any way to temporarily make the node under maintenance invisible  from
>> "nodetool status" output?
>>
>
> I don't think so.
> I would use a different approach like for example only warn/email when the
> node is down for 30 seconds or a minute depending on how long it takes for
> your nodes to restart. This way the failure is not invisible, but ignored
> when only bouncing the nodes.
>
> As a side note, be aware that the 'nodetool status' only give a view of
> the cluster from a specific node, that can be completely wrong as well :).
>
> C*heers,
> ---
> Alain Rodriguez - al...@thelastpickle.com
> France / Spain
>
> The Last Pickle - Apache Cassandra Consulting
> http://www.thelastpickle.com
> <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.thelastpickle.com=DwMFaQ=udBTRvFvXC5Dhqg7UHpJlPps3mZ3LRxpb6__0PomBTQ=JaNakyvP8b5eGvWhmxll6L4SNrrqHGq3Ghe3-Mb4Nezhm-3SiJqFhK3ICb6tsog4=S2-OqjW2Id1W7TR4eOkeKO-1Y4Ta4manIVqNwup837Y=L19bvNHb2aQ5bmAlbs7W-2KcLPcxqRz0XTdX--DKHcI=>
>
> Le ven. 26 oct. 2018 à 15:16, Saha, Sushanta K <
> sushanta.s...@verizonwireless.com> a écrit :
>
>> I have script that parses "nodetool status" output and emails alerts if
>> any node is down. So, when I stop cassandra on a node for maintenance, all
>> nodes stats emailing alarms.
>>
>> Any way to temporarily make the node under maintenance invisible  from
>> "nodetool status" output?
>>
>> Thanks
>>
>>

-- 

*Sushanta Saha|*MTS IV-Cslt-Sys Engrg|WebIaaS_DB Group|HQ -
* VerizonWireless O 770.797.1260  C 770.714.6555 Iaas Support Line
949-286-8810*

nodetool status and node maintenance

[Saha, Sushanta K]

I have script that parses "nodetool status" output and emails alerts if any
node is down. So, when I stop cassandra on a node for maintenance, all
nodes stats emailing alarms.

Any way to temporarily make the node under maintenance invisible  from
"nodetool status" output?

Thanks