Re: Service discovery in the Cassandra cluster

[Jon Haddad]

You’re free to supply your own Seed Provider.  The Seed provider that comes 
with cassandra needs hard coded IPs, but there’s no reason why it has to be 
that way.  

There’s a handful of ideas here: 
https://issues.apache.org/jira/browse/CASSANDRA-12627 


Feel free to experiment, and good luck.

> On May 2, 2017, at 6:48 PM, Roman Naumenko  wrote:
> 
> Service discovery (aka "note some IPs") should be part of the cluster 
> bootstrapping and management.
> 
> See for example how elastic is doing this. Or consul. Its pretty standard 
> practice these days.
> 
> --
> Roman
> 
> On Tue, May 2, 2017 at 5:08 PM Steve Robenalt  > wrote:
> Hi Roman,
> 
> I'm assuming you were intending your first statement to be in jest, but it's 
> really not that hard to startup a Cassandra cluster. The defaults are pretty 
> usable, so if all you want to do is set the IPs and start it up, the cluster 
> probably will just take care of everything else.
> 
> So I jest a little bit too. It's normally desirable to set up storage 
> properly for your database, and there's a few options for which you might 
> want to change the defaults, such as the snitch. 
> 
> Still, if that means you only need to take note of of a couple of IPs and 
> designate them as seeds so your cluster can mostly manage itself, you can say 
> that's sad, but I'd say it's a small price to pay for all that you don't have 
> to do.
> 
> Steve
> 
> On Mon, May 1, 2017 at 4:55 PM, Roman Naumenko  > wrote:
> Lol yeah, why 
> I guess I run some ec2 instances, drop some cassandra deb packages on 'em - 
> the thing will figure out how to run...
> 
> Also, how would you get "initial state of the cluster" if the cluster... is 
> being initialized? 
> Or that's easy, according to the docs - just hardcode some seed IPs into each 
> node, lol
> 
> It's all kinda funny, but in a sad way.
> 
> On Mon, May 1, 2017 at 4:45 PM, Jon Haddad  > wrote:
> Why do you have to figure out what’s up w/ them by accident?  You’ve gotten 
> all the information you need.  Seeds are used to get the initial state of the 
> cluster and as an optimization to spread gossip faster.  That’s it.  
> 
> 
> 
>> On May 1, 2017, at 4:37 PM, Roman Naumenko > > wrote:
>> 
>> Well, I guess I have to figure out what’s up with IPs/hostnames by 
>> experiment.
>> Information about service discovery is practically absent.
>> Not to mention all important details about fqdns/hostnames, automatic 
>> replacing seed nodes or what not. 
>> 
>> —
>> Roman
>> 
>>> On May 1, 2017, at 4:14 PM, Jon Haddad >> > wrote:
>>> 
>>> The in-tree docs do not mention this anywhere, and even have some of the 
>>> answers you’re asking:
>>> 
>>> https://cassandra.apache.org/doc/latest/faq/index.html?highlight=seed#what-are-seeds
>>>  
>>> 
>>> 
>>> The DataStax docs are maintained outside of the project, you’ll have to ask 
>>> them why they’re wrong or misleading.
>>> 
>>> Jon
>>> 
 On May 1, 2017, at 4:10 PM, Roman Naumenko > wrote:
 
 The docs mention IP addresses everywhere.
 
 http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_seed_node.html
  
 
 Promote an existing node to a seed node by adding its IP address to -seeds 
 list and remove (demote) the IP address of the dead seed node from the 
 cassandra.yaml file for each node in the cluster.
 
 http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_node_t.html
  
 
 Note the Address of the dead node; it is used in step 5.
 
 http://docs.datastax.com/en/cassandra/2.1/cassandra/initialize/initializeSingleDS.html
  
 
> Properties to set:
> num_tokens: recommended value: 256
> -seeds: internal IP address of each seed node
 
 I saw also hostnames mentioned few times, but it just makes it even more 
 confusing.
 
 —
 Roman
 
> On May 1, 2017, at 3:50 PM, Jon Haddad  > wrote:
> 
> Sure, you could use DNS.  Where does it say IP addresses are a 
> requirement?
> 
>> On May 1, 2017, at 1:36 PM, Roman Naumenko 

Re: Service discovery in the Cassandra cluster

[Roman Naumenko]

Service discovery (aka "note some IPs") should be part of the cluster
bootstrapping and management.

See for example how elastic is doing this. Or consul. Its pretty standard
practice these days.

--
Roman

On Tue, May 2, 2017 at 5:08 PM Steve Robenalt 
wrote:

> Hi Roman,
>
> I'm assuming you were intending your first statement to be in jest, but
> it's really not that hard to startup a Cassandra cluster. The defaults are
> pretty usable, so if all you want to do is set the IPs and start it up, the
> cluster probably will just take care of everything else.
>
> So I jest a little bit too. It's normally desirable to set up storage
> properly for your database, and there's a few options for which you might
> want to change the defaults, such as the snitch.
>
> Still, if that means you only need to take note of of a couple of IPs and
> designate them as seeds so your cluster can mostly manage itself, you can
> say that's sad, but I'd say it's a small price to pay for all that you
> don't have to do.
>
> Steve
>
> On Mon, May 1, 2017 at 4:55 PM, Roman Naumenko 
> wrote:
>
>> Lol yeah, why
>> I guess I run some ec2 instances, drop some cassandra deb packages on 'em
>> - the thing will figure out how to run...
>>
>> Also, how would you get "initial state of the cluster" if the cluster...
>> is being initialized?
>> Or that's easy, according to the docs - just hardcode some seed IPs into
>> each node, lol
>>
>> It's all kinda funny, but in a sad way.
>>
>> On Mon, May 1, 2017 at 4:45 PM, Jon Haddad 
>> wrote:
>>
>>> Why do you have to figure out what’s up w/ them by accident?  You’ve
>>> gotten all the information you need.  Seeds are used to get the initial
>>> state of the cluster and as an optimization to spread gossip faster.
>>> That’s it.
>>>
>>>
>>>
>>> On May 1, 2017, at 4:37 PM, Roman Naumenko  wrote:
>>>
>>> Well, I guess I have to figure out what’s up with IPs/hostnames by
>>> experiment.
>>> Information about service discovery is practically absent.
>>> Not to mention all important details about fqdns/hostnames, automatic
>>> replacing seed nodes or what not.
>>>
>>> —
>>> Roman
>>>
>>> On May 1, 2017, at 4:14 PM, Jon Haddad 
>>> wrote:
>>>
>>> The in-tree docs do not mention this anywhere, and even have some of the
>>> answers you’re asking:
>>>
>>>
>>> https://cassandra.apache.org/doc/latest/faq/index.html?highlight=seed#what-are-seeds
>>>
>>> The DataStax docs are maintained outside of the project, you’ll have to
>>> ask them why they’re wrong or misleading.
>>>
>>> Jon
>>>
>>> On May 1, 2017, at 4:10 PM, Roman Naumenko  wrote:
>>>
>>> The docs mention IP addresses everywhere.
>>>
>>>
>>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_seed_node.html
>>> Promote an existing node to a seed node by adding its IP address to
>>> -seeds list and remove (demote) the IP address of the dead seed node from
>>> the cassandra.yaml file for each node in the cluster.
>>>
>>>
>>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_node_t.html
>>> Note the Address of the dead node; it is used in step 5.
>>>
>>>
>>> http://docs.datastax.com/en/cassandra/2.1/cassandra/initialize/initializeSingleDS.html
>>>
>>> Properties to set:
>>> num_tokens: recommended value: 256
>>> -seeds: internal IP address of each seed node
>>>
>>>
>>> I saw also *hostnames *mentioned few times, but it just makes it even
>>> more confusing.
>>>
>>> —
>>> Roman
>>>
>>> On May 1, 2017, at 3:50 PM, Jon Haddad 
>>> wrote:
>>>
>>> Sure, you could use DNS.  Where does it say IP addresses are a
>>> requirement?
>>>
>>> On May 1, 2017, at 1:36 PM, Roman Naumenko  wrote:
>>>
>>> If I understand how Cassandra nodes work, they must contain a list of
>>> seed’s IP addressed in config file.
>>>
>>> This requirement makes cluster setup unnecessarily complicated. Is it
>>> possible to use DNS name for seed nodes?
>>>
>>> Thanks,
>>>
>>> —
>>> Roman
>>> -
>>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
>>> For additional commands, e-mail: user-h...@cassandra.apache.org
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>
>
> --
>
>
> * Steve Robenalt Software Architect, HighWire Press, Inc. *
> www.highwire.org| Los Gatos, CA| Belfast, NI| Brighton, UK
> 
> 
>
> *HighWire Summer Publishers' Meeting, London, June 12-13
> *
> STM Annual US Conference, April 25-27: Michiel Klein Swormink and Jennifer
> Chang are representing HighWire
> 
> 2017 CSE Annual Meeting: John Sack is presenting on 

Re: Service discovery in the Cassandra cluster

[daemeon reiydelle]

My compliments to all of you for being adults, excessively kind, and
definitely excessively nice.


*...*



*Daemeon C.M. ReiydelleUSA (+1) 415.501.0198London (+44) (0) 20 8144 9872*

On Tue, May 2, 2017 at 5:08 PM, Steve Robenalt 
wrote:

> Hi Roman,
>
> I'm assuming you were intending your first statement to be in jest, but
> it's really not that hard to startup a Cassandra cluster. The defaults are
> pretty usable, so if all you want to do is set the IPs and start it up, the
> cluster probably will just take care of everything else.
>
> So I jest a little bit too. It's normally desirable to set up storage
> properly for your database, and there's a few options for which you might
> want to change the defaults, such as the snitch.
>
> Still, if that means you only need to take note of of a couple of IPs and
> designate them as seeds so your cluster can mostly manage itself, you can
> say that's sad, but I'd say it's a small price to pay for all that you
> don't have to do.
>
> Steve
>
> On Mon, May 1, 2017 at 4:55 PM, Roman Naumenko 
> wrote:
>
>> Lol yeah, why
>> I guess I run some ec2 instances, drop some cassandra deb packages on 'em
>> - the thing will figure out how to run...
>>
>> Also, how would you get "initial state of the cluster" if the cluster...
>> is being initialized?
>> Or that's easy, according to the docs - just hardcode some seed IPs into
>> each node, lol
>>
>> It's all kinda funny, but in a sad way.
>>
>> On Mon, May 1, 2017 at 4:45 PM, Jon Haddad 
>> wrote:
>>
>>> Why do you have to figure out what’s up w/ them by accident?  You’ve
>>> gotten all the information you need.  Seeds are used to get the initial
>>> state of the cluster and as an optimization to spread gossip faster.
>>> That’s it.
>>>
>>>
>>>
>>> On May 1, 2017, at 4:37 PM, Roman Naumenko  wrote:
>>>
>>> Well, I guess I have to figure out what’s up with IPs/hostnames by
>>> experiment.
>>> Information about service discovery is practically absent.
>>> Not to mention all important details about fqdns/hostnames, automatic
>>> replacing seed nodes or what not.
>>>
>>> —
>>> Roman
>>>
>>> On May 1, 2017, at 4:14 PM, Jon Haddad 
>>> wrote:
>>>
>>> The in-tree docs do not mention this anywhere, and even have some of the
>>> answers you’re asking:
>>>
>>> https://cassandra.apache.org/doc/latest/faq/index.html?highl
>>> ight=seed#what-are-seeds
>>>
>>> The DataStax docs are maintained outside of the project, you’ll have to
>>> ask them why they’re wrong or misleading.
>>>
>>> Jon
>>>
>>> On May 1, 2017, at 4:10 PM, Roman Naumenko  wrote:
>>>
>>> The docs mention IP addresses everywhere.
>>>
>>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra
>>> /operations/ops_replace_seed_node.html
>>> Promote an existing node to a seed node by adding its IP address to
>>> -seeds list and remove (demote) the IP address of the dead seed node from
>>> the cassandra.yaml file for each node in the cluster.
>>>
>>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra
>>> /operations/ops_replace_node_t.html
>>> Note the Address of the dead node; it is used in step 5.
>>>
>>> http://docs.datastax.com/en/cassandra/2.1/cassandra/initiali
>>> ze/initializeSingleDS.html
>>>
>>> Properties to set:
>>> num_tokens: recommended value: 256
>>> -seeds: internal IP address of each seed node
>>>
>>>
>>> I saw also *hostnames *mentioned few times, but it just makes it even
>>> more confusing.
>>>
>>> —
>>> Roman
>>>
>>> On May 1, 2017, at 3:50 PM, Jon Haddad 
>>> wrote:
>>>
>>> Sure, you could use DNS.  Where does it say IP addresses are a
>>> requirement?
>>>
>>> On May 1, 2017, at 1:36 PM, Roman Naumenko  wrote:
>>>
>>> If I understand how Cassandra nodes work, they must contain a list of
>>> seed’s IP addressed in config file.
>>>
>>> This requirement makes cluster setup unnecessarily complicated. Is it
>>> possible to use DNS name for seed nodes?
>>>
>>> Thanks,
>>>
>>> —
>>> Roman
>>> -
>>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
>>> For additional commands, e-mail: user-h...@cassandra.apache.org
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>
>
> --
>
>
> * Steve Robenalt Software Architect, HighWire Press, Inc. *
> www.highwire.org| Los Gatos, CA| Belfast, NI| Brighton, UK
> 
> 
>
> *HighWire Summer Publishers' Meeting, London, June 12-13
> *
> STM Annual US Conference, April 25-27: Michiel Klein Swormink and Jennifer
> Chang are representing HighWire
> 
> 2017 CSE Annual Meeting: John Sack is presenting on topic of 

Re: Service discovery in the Cassandra cluster

[Steve Robenalt]

Hi Roman,

I'm assuming you were intending your first statement to be in jest, but
it's really not that hard to startup a Cassandra cluster. The defaults are
pretty usable, so if all you want to do is set the IPs and start it up, the
cluster probably will just take care of everything else.

So I jest a little bit too. It's normally desirable to set up storage
properly for your database, and there's a few options for which you might
want to change the defaults, such as the snitch.

Still, if that means you only need to take note of of a couple of IPs and
designate them as seeds so your cluster can mostly manage itself, you can
say that's sad, but I'd say it's a small price to pay for all that you
don't have to do.

Steve

On Mon, May 1, 2017 at 4:55 PM, Roman Naumenko  wrote:

> Lol yeah, why
> I guess I run some ec2 instances, drop some cassandra deb packages on 'em
> - the thing will figure out how to run...
>
> Also, how would you get "initial state of the cluster" if the cluster...
> is being initialized?
> Or that's easy, according to the docs - just hardcode some seed IPs into
> each node, lol
>
> It's all kinda funny, but in a sad way.
>
> On Mon, May 1, 2017 at 4:45 PM, Jon Haddad 
> wrote:
>
>> Why do you have to figure out what’s up w/ them by accident?  You’ve
>> gotten all the information you need.  Seeds are used to get the initial
>> state of the cluster and as an optimization to spread gossip faster.
>> That’s it.
>>
>>
>>
>> On May 1, 2017, at 4:37 PM, Roman Naumenko  wrote:
>>
>> Well, I guess I have to figure out what’s up with IPs/hostnames by
>> experiment.
>> Information about service discovery is practically absent.
>> Not to mention all important details about fqdns/hostnames, automatic
>> replacing seed nodes or what not.
>>
>> —
>> Roman
>>
>> On May 1, 2017, at 4:14 PM, Jon Haddad  wrote:
>>
>> The in-tree docs do not mention this anywhere, and even have some of the
>> answers you’re asking:
>>
>> https://cassandra.apache.org/doc/latest/faq/index.html?highl
>> ight=seed#what-are-seeds
>>
>> The DataStax docs are maintained outside of the project, you’ll have to
>> ask them why they’re wrong or misleading.
>>
>> Jon
>>
>> On May 1, 2017, at 4:10 PM, Roman Naumenko  wrote:
>>
>> The docs mention IP addresses everywhere.
>>
>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra
>> /operations/ops_replace_seed_node.html
>> Promote an existing node to a seed node by adding its IP address to
>> -seeds list and remove (demote) the IP address of the dead seed node from
>> the cassandra.yaml file for each node in the cluster.
>>
>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra
>> /operations/ops_replace_node_t.html
>> Note the Address of the dead node; it is used in step 5.
>>
>> http://docs.datastax.com/en/cassandra/2.1/cassandra/initiali
>> ze/initializeSingleDS.html
>>
>> Properties to set:
>> num_tokens: recommended value: 256
>> -seeds: internal IP address of each seed node
>>
>>
>> I saw also *hostnames *mentioned few times, but it just makes it even
>> more confusing.
>>
>> —
>> Roman
>>
>> On May 1, 2017, at 3:50 PM, Jon Haddad  wrote:
>>
>> Sure, you could use DNS.  Where does it say IP addresses are a
>> requirement?
>>
>> On May 1, 2017, at 1:36 PM, Roman Naumenko  wrote:
>>
>> If I understand how Cassandra nodes work, they must contain a list of
>> seed’s IP addressed in config file.
>>
>> This requirement makes cluster setup unnecessarily complicated. Is it
>> possible to use DNS name for seed nodes?
>>
>> Thanks,
>>
>> —
>> Roman
>> -
>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
>> For additional commands, e-mail: user-h...@cassandra.apache.org
>>
>>
>>
>>
>>
>>
>>
>


-- 


* Steve Robenalt Software Architect, HighWire Press, Inc. *
www.highwire.org| Los Gatos, CA| Belfast, NI| Brighton, UK



*HighWire Summer Publishers' Meeting, London, June 12-13
*
STM Annual US Conference, April 25-27: Michiel Klein Swormink and Jennifer
Chang are representing HighWire

2017 CSE Annual Meeting: John Sack is presenting on topic of Piracy, May 23

SSP Annual Meeting, May 31-June 2: *Visit HighWire on Booth #101A*

Re: Service discovery in the Cassandra cluster

[Roman Naumenko]

Lol yeah, why
I guess I run some ec2 instances, drop some cassandra deb packages on 'em -
the thing will figure out how to run...

Also, how would you get "initial state of the cluster" if the cluster... is
being initialized?
Or that's easy, according to the docs - just hardcode some seed IPs into
each node, lol

It's all kinda funny, but in a sad way.

On Mon, May 1, 2017 at 4:45 PM, Jon Haddad 
wrote:

> Why do you have to figure out what’s up w/ them by accident?  You’ve
> gotten all the information you need.  Seeds are used to get the initial
> state of the cluster and as an optimization to spread gossip faster.
> That’s it.
>
>
>
> On May 1, 2017, at 4:37 PM, Roman Naumenko  wrote:
>
> Well, I guess I have to figure out what’s up with IPs/hostnames by
> experiment.
> Information about service discovery is practically absent.
> Not to mention all important details about fqdns/hostnames, automatic
> replacing seed nodes or what not.
>
> —
> Roman
>
> On May 1, 2017, at 4:14 PM, Jon Haddad  wrote:
>
> The in-tree docs do not mention this anywhere, and even have some of the
> answers you’re asking:
>
> https://cassandra.apache.org/doc/latest/faq/index.html?
> highlight=seed#what-are-seeds
>
> The DataStax docs are maintained outside of the project, you’ll have to
> ask them why they’re wrong or misleading.
>
> Jon
>
> On May 1, 2017, at 4:10 PM, Roman Naumenko  wrote:
>
> The docs mention IP addresses everywhere.
>
> http://docs.datastax.com/en/archived/cassandra/2.0/
> cassandra/operations/ops_replace_seed_node.html
> Promote an existing node to a seed node by adding its IP address to -seeds
> list and remove (demote) the IP address of the dead seed node from the
> cassandra.yaml file for each node in the cluster.
>
> http://docs.datastax.com/en/archived/cassandra/2.0/
> cassandra/operations/ops_replace_node_t.html
> Note the Address of the dead node; it is used in step 5.
>
> http://docs.datastax.com/en/cassandra/2.1/cassandra/
> initialize/initializeSingleDS.html
>
> Properties to set:
> num_tokens: recommended value: 256
> -seeds: internal IP address of each seed node
>
>
> I saw also *hostnames *mentioned few times, but it just makes it even
> more confusing.
>
> —
> Roman
>
> On May 1, 2017, at 3:50 PM, Jon Haddad  wrote:
>
> Sure, you could use DNS.  Where does it say IP addresses are a requirement?
>
> On May 1, 2017, at 1:36 PM, Roman Naumenko  wrote:
>
> If I understand how Cassandra nodes work, they must contain a list of
> seed’s IP addressed in config file.
>
> This requirement makes cluster setup unnecessarily complicated. Is it
> possible to use DNS name for seed nodes?
>
> Thanks,
>
> —
> Roman
> -
> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
> For additional commands, e-mail: user-h...@cassandra.apache.org
>
>
>
>
>
>
>

Re: Service discovery in the Cassandra cluster

[Jon Haddad]

Why do you have to figure out what’s up w/ them by accident?  You’ve gotten all 
the information you need.  Seeds are used to get the initial state of the 
cluster and as an optimization to spread gossip faster.  That’s it.  



> On May 1, 2017, at 4:37 PM, Roman Naumenko  wrote:
> 
> Well, I guess I have to figure out what’s up with IPs/hostnames by experiment.
> Information about service discovery is practically absent.
> Not to mention all important details about fqdns/hostnames, automatic 
> replacing seed nodes or what not. 
> 
> —
> Roman
> 
>> On May 1, 2017, at 4:14 PM, Jon Haddad > > wrote:
>> 
>> The in-tree docs do not mention this anywhere, and even have some of the 
>> answers you’re asking:
>> 
>> https://cassandra.apache.org/doc/latest/faq/index.html?highlight=seed#what-are-seeds
>>  
>> 
>> 
>> The DataStax docs are maintained outside of the project, you’ll have to ask 
>> them why they’re wrong or misleading.
>> 
>> Jon
>> 
>>> On May 1, 2017, at 4:10 PM, Roman Naumenko >> > wrote:
>>> 
>>> The docs mention IP addresses everywhere.
>>> 
>>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_seed_node.html
>>>  
>>> 
>>> Promote an existing node to a seed node by adding its IP address to -seeds 
>>> list and remove (demote) the IP address of the dead seed node from the 
>>> cassandra.yaml file for each node in the cluster.
>>> 
>>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_node_t.html
>>>  
>>> 
>>> Note the Address of the dead node; it is used in step 5.
>>> 
>>> http://docs.datastax.com/en/cassandra/2.1/cassandra/initialize/initializeSingleDS.html
>>>  
>>> 
 Properties to set:
 num_tokens: recommended value: 256
 -seeds: internal IP address of each seed node
>>> 
>>> I saw also hostnames mentioned few times, but it just makes it even more 
>>> confusing.
>>> 
>>> —
>>> Roman
>>> 
 On May 1, 2017, at 3:50 PM, Jon Haddad > wrote:
 
 Sure, you could use DNS.  Where does it say IP addresses are a requirement?
 
> On May 1, 2017, at 1:36 PM, Roman Naumenko  > wrote:
> 
> If I understand how Cassandra nodes work, they must contain a list of 
> seed’s IP addressed in config file.
> 
> This requirement makes cluster setup unnecessarily complicated. Is it 
> possible to use DNS name for seed nodes?
> 
> Thanks,
> 
> —
> Roman
> -
> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org 
> 
> For additional commands, e-mail: user-h...@cassandra.apache.org 
> 
> 
 
>>> 
>> 
> 

Re: Service discovery in the Cassandra cluster

[Roman Naumenko]

Well, I guess I have to figure out what’s up with IPs/hostnames by experiment.
Information about service discovery is practically absent.
Not to mention all important details about fqdns/hostnames, automatic replacing 
seed nodes or what not. 

—
Roman

> On May 1, 2017, at 4:14 PM, Jon Haddad  wrote:
> 
> The in-tree docs do not mention this anywhere, and even have some of the 
> answers you’re asking:
> 
> https://cassandra.apache.org/doc/latest/faq/index.html?highlight=seed#what-are-seeds
>  
> 
> 
> The DataStax docs are maintained outside of the project, you’ll have to ask 
> them why they’re wrong or misleading.
> 
> Jon
> 
>> On May 1, 2017, at 4:10 PM, Roman Naumenko > > wrote:
>> 
>> The docs mention IP addresses everywhere.
>> 
>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_seed_node.html
>>  
>> 
>> Promote an existing node to a seed node by adding its IP address to -seeds 
>> list and remove (demote) the IP address of the dead seed node from the 
>> cassandra.yaml file for each node in the cluster.
>> 
>> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_node_t.html
>>  
>> 
>> Note the Address of the dead node; it is used in step 5.
>> 
>> http://docs.datastax.com/en/cassandra/2.1/cassandra/initialize/initializeSingleDS.html
>>  
>> 
>>> Properties to set:
>>> num_tokens: recommended value: 256
>>> -seeds: internal IP address of each seed node
>> 
>> I saw also hostnames mentioned few times, but it just makes it even more 
>> confusing.
>> 
>> —
>> Roman
>> 
>>> On May 1, 2017, at 3:50 PM, Jon Haddad >> > wrote:
>>> 
>>> Sure, you could use DNS.  Where does it say IP addresses are a requirement?
>>> 
 On May 1, 2017, at 1:36 PM, Roman Naumenko > wrote:
 
 If I understand how Cassandra nodes work, they must contain a list of 
 seed’s IP addressed in config file.
 
 This requirement makes cluster setup unnecessarily complicated. Is it 
 possible to use DNS name for seed nodes?
 
 Thanks,
 
 —
 Roman
 -
 To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org 
 
 For additional commands, e-mail: user-h...@cassandra.apache.org 
 
 
>>> 
>> 
> 

Re: Service discovery in the Cassandra cluster

[Jon Haddad]

The in-tree docs do not mention this anywhere, and even have some of the 
answers you’re asking:

https://cassandra.apache.org/doc/latest/faq/index.html?highlight=seed#what-are-seeds
 


The DataStax docs are maintained outside of the project, you’ll have to ask 
them why they’re wrong or misleading.

Jon

> On May 1, 2017, at 4:10 PM, Roman Naumenko  wrote:
> 
> The docs mention IP addresses everywhere.
> 
> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_seed_node.html
>  
> 
> Promote an existing node to a seed node by adding its IP address to -seeds 
> list and remove (demote) the IP address of the dead seed node from the 
> cassandra.yaml file for each node in the cluster.
> 
> http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_node_t.html
>  
> 
> Note the Address of the dead node; it is used in step 5.
> 
> http://docs.datastax.com/en/cassandra/2.1/cassandra/initialize/initializeSingleDS.html
>  
> 
>> Properties to set:
>> num_tokens: recommended value: 256
>> -seeds: internal IP address of each seed node
> 
> I saw also hostnames mentioned few times, but it just makes it even more 
> confusing.
> 
> —
> Roman
> 
>> On May 1, 2017, at 3:50 PM, Jon Haddad > > wrote:
>> 
>> Sure, you could use DNS.  Where does it say IP addresses are a requirement?
>> 
>>> On May 1, 2017, at 1:36 PM, Roman Naumenko >> > wrote:
>>> 
>>> If I understand how Cassandra nodes work, they must contain a list of 
>>> seed’s IP addressed in config file.
>>> 
>>> This requirement makes cluster setup unnecessarily complicated. Is it 
>>> possible to use DNS name for seed nodes?
>>> 
>>> Thanks,
>>> 
>>> —
>>> Roman
>>> -
>>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org 
>>> 
>>> For additional commands, e-mail: user-h...@cassandra.apache.org 
>>> 
>>> 
>> 
> 

Re: Service discovery in the Cassandra cluster

[Roman Naumenko]

The docs mention IP addresses everywhere.

http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_seed_node.html
 

Promote an existing node to a seed node by adding its IP address to -seeds list 
and remove (demote) the IP address of the dead seed node from the 
cassandra.yaml file for each node in the cluster.

http://docs.datastax.com/en/archived/cassandra/2.0/cassandra/operations/ops_replace_node_t.html
 

Note the Address of the dead node; it is used in step 5.

http://docs.datastax.com/en/cassandra/2.1/cassandra/initialize/initializeSingleDS.html
 

> Properties to set:
> num_tokens: recommended value: 256
> -seeds: internal IP address of each seed node

I saw also hostnames mentioned few times, but it just makes it even more 
confusing.

—
Roman

> On May 1, 2017, at 3:50 PM, Jon Haddad  wrote:
> 
> Sure, you could use DNS.  Where does it say IP addresses are a requirement?
> 
>> On May 1, 2017, at 1:36 PM, Roman Naumenko  wrote:
>> 
>> If I understand how Cassandra nodes work, they must contain a list of seed’s 
>> IP addressed in config file.
>> 
>> This requirement makes cluster setup unnecessarily complicated. Is it 
>> possible to use DNS name for seed nodes?
>> 
>> Thanks,
>> 
>> —
>> Roman
>> -
>> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
>> For additional commands, e-mail: user-h...@cassandra.apache.org
>> 
> 

Re: Service discovery in the Cassandra cluster

[daemeon reiydelle]

Yes, you can use host names. That merely adds another level of
configuration. When using terraform, I often use node names like
 and just use those. They are only routable within the
region/VPC but are in fact already in dns. You do have to watch out as if
you change the seeds (in tf) or the cluster can get terminated and rebuild.
If you have a way to capture these (you can do it in ansible, I had been
told it is really hard to do in Chef/Puppet) then your cms can just adjust
the xml as needed without fussing with route53.


*...*



*Daemeon C.M. ReiydelleUSA (+1) 415.501.0198London (+44) (0) 20 8144 9872*

On Mon, May 1, 2017 at 3:50 PM, Jon Haddad 
wrote:

> Sure, you could use DNS.  Where does it say IP addresses are a requirement?
>
> > On May 1, 2017, at 1:36 PM, Roman Naumenko  wrote:
> >
> > If I understand how Cassandra nodes work, they must contain a list of
> seed’s IP addressed in config file.
> >
> > This requirement makes cluster setup unnecessarily complicated. Is it
> possible to use DNS name for seed nodes?
> >
> > Thanks,
> >
> > —
> > Roman
> > -
> > To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
> > For additional commands, e-mail: user-h...@cassandra.apache.org
> >
>
>
> -
> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
> For additional commands, e-mail: user-h...@cassandra.apache.org
>
>

Re: Service discovery in the Cassandra cluster

[Jon Haddad]

Sure, you could use DNS.  Where does it say IP addresses are a requirement?

> On May 1, 2017, at 1:36 PM, Roman Naumenko  wrote:
> 
> If I understand how Cassandra nodes work, they must contain a list of seed’s 
> IP addressed in config file.
> 
> This requirement makes cluster setup unnecessarily complicated. Is it 
> possible to use DNS name for seed nodes?
> 
> Thanks,
> 
> —
> Roman
> -
> To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
> For additional commands, e-mail: user-h...@cassandra.apache.org
> 


-
To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
For additional commands, e-mail: user-h...@cassandra.apache.org

Service discovery in the Cassandra cluster

[Roman Naumenko]

If I understand how Cassandra nodes work, they must contain a list of seed’s IP 
addressed in config file.

This requirement makes cluster setup unnecessarily complicated. Is it possible 
to use DNS name for seed nodes?

Thanks,

—
Roman
-
To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org
For additional commands, e-mail: user-h...@cassandra.apache.org