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From Affan Syed <as...@an10.io>
Subject Re: Convert single node C* to cluster (rebalancing problem)
Date Thu, 15 Jun 2017 05:54:36 GMT
John,

I am a co-worker with Junaid -- he is out sick, so just wanted to confirm
that one of your shots in the dark is correct. This is a RF of 1x

"CREATE KEYSPACE orion WITH replication = {'class': 'SimpleStrategy',
'replication_factor': '1'}  AND durable_writes = true;"

However, how does the RF affect the redistribution of key/data?

Affan

- Affan

On Wed, Jun 14, 2017 at 1:16 AM, John Hughes <johnthughes@gmail.com> wrote:

> OP, I was just looking at your original numbers and I have some questions:
>
> 270GB on one node and 414KB on the other, but something close to 50/50 on
> "Owns(effective)".
> What replication factor are your keyspaces set up with? 1x or 2x or ??
>
> I would say you are seeing 50/50 because the tokens are allocated
> 50/50(others on the list please correct what are for me really just
> assumptions!!!!), but I would hazard a guess that your replication factor
> is still 1x, so it isn't moving anything around. Or your keyspace
> rplication is incorrect and isn't being distributed(I have had issues with
> the AWSMultiRegionSnitch and not getting the region correct[us-east vs
> us-east-1). It doesn't throw an error, but it doesn't work very well either
> =)
>
> Can you do a 'describe keyspace XXX' and show the first line(the CREATE
> KEYSPACE line).
>
> Mind you, these are all just shots in the dark from here.
>
> Cheers,
>
>
> On Tue, Jun 13, 2017 at 3:13 AM Junaid Nasir <jnasir@an10.io> wrote:
>
>> Is the OP expecting a perfect 50%/50% split?
>>
>>
>> best result I got was 240gb/30gb split, which I think is not properly
>> balanced.
>>
>>
>>> Also, what are your outputs when you call out specific keyspaces? Do the
>>> numbers get more even?
>>
>>
>> i don't know what you mean by *call out specific key spaces?* can you
>> please explain that a bit.
>>
>>
>> If your schema is not modelled correctly you can easily end up unevenly
>>> distributed data.
>>
>>
>> I think that is the problem. initial 270gb data might not by modeled
>> correctly. I have run a lot of tests on 270gb data including downsizing it
>> to 5gb, they all resulted in same uneven distribution. I also tested a
>> dummy dataset of 2gb which was balanced evenly. coming from rdb, I didn't
>> give much thought to data modeling. can anyone please point me to some
>> resources regarding this problem.
>>
>> On Tue, Jun 13, 2017 at 3:24 AM, Akhil Mehra <akhilmehra@gmail.com>
>> wrote:
>>
>>> Great point John.
>>>
>>> The OP should also note that data distribution also depends on your
>>> schema and incoming data profile.
>>>
>>> If your schema is not modelled correctly you can easily end up unevenly
>>> distributed data.
>>>
>>> Cheers,
>>> Akhil
>>>
>>> On Tue, Jun 13, 2017 at 3:36 AM, John Hughes <johnthughes@gmail.com>
>>> wrote:
>>>
>>>> Is the OP expecting a perfect 50%/50% split? That, to my experience, is
>>>> not going to happen, it is almost always shifted from a fraction of a
>>>> percent to a couple percent.
>>>>
>>>> Datacenter: eu-west
>>>> ===================
>>>> Status=Up/Down
>>>> |/ State=Normal/Leaving/Joining/Moving
>>>> --  Address        Load       Tokens       Owns (effective)  Host ID
>>>>                             Rack
>>>> UN  XX.XX.XX.XX    22.71 GiB  256          47.6%
>>>> 57dafdde-2f62-467c-a8ff-c91e712f89c9  1c
>>>> UN  XX.XX.XX.XX  17.17 GiB  256          51.3%
>>>> d2a65c51-087d-48de-ae1f-a41142eb148d  1b
>>>> UN  XX.XX.XX.XX  26.15 GiB  256          52.4%
>>>> acf5dd34-5b81-4e5b-b7be-85a7fccd8e1c  1c
>>>> UN  XX.XX.XX.XX   16.64 GiB  256          50.2%
>>>> 6c8842dd-a966-467c-a7bc-bd6269ce3e7e  1a
>>>> UN  XX.XX.XX.XX  24.39 GiB  256          49.8%
>>>> fd92525d-edf2-4974-8bc5-a350a8831dfa  1a
>>>> UN  XX.XX.XX.XX   23.8 GiB   256          48.7%
>>>> bdc597c0-718c-4ef6-b3ef-7785110a9923  1b
>>>>
>>>> Though maybe part of what you are experiencing can be cleared up by
>>>> repair/compaction/cleanup. Also, what are your outputs when you call out
>>>> specific keyspaces? Do the numbers get more even?
>>>>
>>>> Cheers,
>>>>
>>>> On Mon, Jun 12, 2017 at 5:22 AM Akhil Mehra <akhilmehra@gmail.com>
>>>> wrote:
>>>>
>>>>> auto_bootstrap is true by default. Ensure its set to true. On startup
>>>>> look at your logs for your auto_bootstrap value.  Look at the node
>>>>> configuration line in your log file.
>>>>>
>>>>> Akhil
>>>>>
>>>>> On Mon, Jun 12, 2017 at 6:18 PM, Junaid Nasir <jnasir@an10.io>
wrote:
>>>>>
>>>>>> No, I didn't set it (left it at default value)
>>>>>>
>>>>>> On Fri, Jun 9, 2017 at 3:18 AM, ZAIDI, ASAD A <az192g@att.com>
wrote:
>>>>>>
>>>>>>> Did you make sure auto_bootstrap property is indeed set to [true]
>>>>>>> when you added the node?
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> *From:* Junaid Nasir [mailto:jnasir@an10.io]
>>>>>>> *Sent:* Monday, June 05, 2017 6:29 AM
>>>>>>> *To:* Akhil Mehra <akhilmehra@gmail.com>
>>>>>>> *Cc:* Vladimir Yudovin <vladyu@winguzone.com>;
>>>>>>> user@cassandra.apache.org
>>>>>>> *Subject:* Re: Convert single node C* to cluster (rebalancing
>>>>>>> problem)
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> not evenly, i have setup a new cluster with subset of data (around
>>>>>>> 5gb). using the configuration above I am getting these results
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Datacenter: datacenter1
>>>>>>>
>>>>>>> =======================
>>>>>>>
>>>>>>> Status=Up/Down
>>>>>>>
>>>>>>> |/ State=Normal/Leaving/Joining/Moving
>>>>>>>
>>>>>>> --  Address      Load       Tokens       Owns (effective)  Host
ID     Rack
>>>>>>>
>>>>>>> UN  10.128.2.1   4.86 GiB   256          44.9%             e4427611-c247-42ee-9404-371e177f5f17
 rack1
>>>>>>>
>>>>>>> UN  10.128.2.10  725.03 MiB  256         55.1%             690d5620-99d3-4ae3-aebe-8f33af54a08b
 rack1
>>>>>>>
>>>>>>> is there anything else I can tweak/check to make the distribution
>>>>>>> even?
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Sat, Jun 3, 2017 at 3:30 AM, Akhil Mehra <akhilmehra@gmail.com>
>>>>>>> wrote:
>>>>>>>
>>>>>>> So now the data is evenly balanced in both nodes?
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Refer to the following documentation to get a better understanding
>>>>>>> of the roc_address and the broadcast_rpc_address https://
>>>>>>> www.instaclustr.com/demystifying-cassandras-broadcast_address/
>>>>>>> <https://urldefense.proofpoint.com/v2/url?u=https-3A__www.instaclustr.com_demystifying-2Dcassandras-2Dbroadcast-5Faddress_&d=DwMFaQ&c=LFYZ-o9_HUMeMTSQicvjIg&r=FsmDztdsVuIKml8IDhdHdg&m=57WqcUduTb1GA2Ij5E1fXgw3Cf21HYBK_4l2HVryPrk&s=MaTA43pugg78xQNfaOQElhyvd8k7CjVqZPr3IWALdWI&e=>.
>>>>>>> I am surprised that your node started up with rpc_broadcast_address
>>>>>>> set as this is an unsupported property. I am assuming you are
using
>>>>>>> Cassandra version 3.10.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Regards,
>>>>>>>
>>>>>>> Akhil
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On 2/06/2017, at 11:06 PM, Junaid Nasir <jnasir@an10.io>
wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> I am able to get it working. I added a new node with following
>>>>>>> changes
>>>>>>>
>>>>>>> #rpc_address:0.0.0.0
>>>>>>>
>>>>>>> rpc_address: 10.128.1.11
>>>>>>>
>>>>>>> #rpc_broadcast_address:10.128.1.11
>>>>>>>
>>>>>>> rpc_address was set to 0.0.0.0, (I ran into a problem previously
>>>>>>> regarding remote connection and made these changes
>>>>>>> https://stackoverflow.com/questions/12236898/apache-
>>>>>>> cassandra-remote-access
>>>>>>> <https://urldefense.proofpoint.com/v2/url?u=https-3A__stackoverflow.com_questions_12236898_apache-2Dcassandra-2Dremote-2Daccess&d=DwMFaQ&c=LFYZ-o9_HUMeMTSQicvjIg&r=FsmDztdsVuIKml8IDhdHdg&m=57WqcUduTb1GA2Ij5E1fXgw3Cf21HYBK_4l2HVryPrk&s=oj8BCLiyBDqqVQNqfGohFeujtqlzAkd-uwS878d4mg4&e=>
>>>>>>> )
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> should it be happening?
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> On Thu, Jun 1, 2017 at 6:31 PM, Vladimir Yudovin <
>>>>>>> vladyu@winguzone.com> wrote:
>>>>>>>
>>>>>>> Did you run "nodetool cleanup" on first node after second was
>>>>>>> bootstrapped? It should clean rows not belonging to node after
tokens
>>>>>>> changed.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Best regards, Vladimir Yudovin,
>>>>>>>
>>>>>>> *Winguzone
>>>>>>> <https://urldefense.proofpoint.com/v2/url?u=https-3A__winguzone.com_-3Ffrom-3Dlist&d=DwMFaQ&c=LFYZ-o9_HUMeMTSQicvjIg&r=FsmDztdsVuIKml8IDhdHdg&m=57WqcUduTb1GA2Ij5E1fXgw3Cf21HYBK_4l2HVryPrk&s=Q1M5YRAsw0iUQKOIulEmO72RhdENQCRhpqZSjgxxHos&e=>
>>>>>>> - Cloud Cassandra Hosting*
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> ---- On Wed, 31 May 2017 03:55:54 -0400 *Junaid Nasir
>>>>>>> <jnasir@an10.io <jnasir@an10.io>>* wrote ----
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> Cassandra ensure that adding or removing nodes are very easy
and
>>>>>>> that load is balanced between nodes when a change is made. but
it's not
>>>>>>> working in my case.
>>>>>>>
>>>>>>> I have a single node C* deployment (with 270 GB of data) and
want to
>>>>>>> load balance the data on multiple nodes, I followed this guide
>>>>>>> <https://urldefense.proofpoint.com/v2/url?u=https-3A__docs.datastax.com_en_cassandra_2.1_cassandra_operations_ops-5Fadd-5Fnode-5Fto-5Fcluster-5Ft.html&d=DwMFaQ&c=LFYZ-o9_HUMeMTSQicvjIg&r=FsmDztdsVuIKml8IDhdHdg&m=57WqcUduTb1GA2Ij5E1fXgw3Cf21HYBK_4l2HVryPrk&s=xnLuX4qqSZxVuY6Gz2NXRdc6TG8J7at9kDhkhBnWpnM&e=>
>>>>>>>
>>>>>>>
>>>>>>> `nodetool status` shows 2 nodes but load is not balanced between
them
>>>>>>>
>>>>>>> Datacenter: dc1
>>>>>>>
>>>>>>> ===============
>>>>>>>
>>>>>>> Status=Up/Down
>>>>>>>
>>>>>>> |/ State=Normal/Leaving/Joining/Moving
>>>>>>>
>>>>>>> --  Address      Load       Tokens       Owns (effective)  Host
ID    Rack
>>>>>>>
>>>>>>> UN  10.128.0.7   270.75 GiB  256          48.6%        1a3f6faa-4376-45a8-9c20-11480ae5664c
 rack1
>>>>>>>
>>>>>>> UN  10.128.0.14  414.36 KiB  256          51.4%        66a89fbf-08ba-4b5d-9f10-55d52a199b41
 rack1
>>>>>>>
>>>>>>> I also ran 'nodetool repair' on new node but result is same.
any
>>>>>>> pointers would be appreciated :)
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> conf file of new node
>>>>>>>
>>>>>>> cluster_name: 'cluster1'
>>>>>>>
>>>>>>>  - seeds: "10.128.0.7"
>>>>>>> num_tokens: 256
>>>>>>>
>>>>>>> endpoint_snitch: GossipingPropertyFileSnitch
>>>>>>>
>>>>>>> Thanks,
>>>>>>>
>>>>>>> Junaid
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>
>>

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