You are viewing a plain text version of this content. The canonical link for it is here.
Posted to user@cassandra.apache.org by sai krishnam raju potturi <ps...@gmail.com> on 2015/08/28 20:12:00 UTC
Fwd: Re : Restoring nodes in a new datacenter, from snapshots in an
existing datacenter
hi;
We have cassandra cluster with Vnodes spanning across 3 data centers.
We take backup of the snapshots from one datacenter.
In a doomsday scenario, we want to restore a downed datacenter, with
snapshots from another datacenter. We have same number of nodes in each
datacenter.
1 : We know it requires copying the snapshots and their corresponding token
ranges to the nodes in new datacenter, and running nodetool refresh.
2 : The question is, we will now have 2 datacenters, with the same exact
token ranges. Will that cause any problem.
DC1 : Node-1 : token1......token10
Node-2 : token11 .....token20
Node-3 : token21 ..... token30
Node-4 : token31 ..... token40
DC2 : Node-1 : token1.....token10
Node-2 : token11....token20
Node-3 : token21....token30
Node-4 : token31....token40
thanks
Sai
Re: Re : Restoring nodes in a new datacenter, from snapshots in an
existing datacenter
Posted by sai krishnam raju potturi <ps...@gmail.com>.
thanks Nate. But regarding our situation, of the 3 Datacenters we have DC1
DC2 and DC3, we take backup of snapshots on DC1.
If DC3 were to go down, will we not be able to bring up a new DC4 with
snapshots and token_ranges from DC1?
On Fri, Aug 28, 2015 at 3:19 PM, Nate McCall <na...@thelastpickle.com> wrote:
> You cannot use the identical token ranges. You have to capture membership
> information somewhere for each datacenter, and use that token information
> when briging up the replacement DC.
>
> You can find details on this process here:
>
> http://docs.datastax.com/en/cassandra/2.0/cassandra/operations/ops_snapshot_restore_new_cluster.html
>
> That process is straight forward, but it can go south pretty quickly if
> you miss a step. It's a really good idea to set asside some time to try
> this out in a staging/test system and build a runbook for the process
> targeting your specific environment.
>
> On Fri, Aug 28, 2015 at 1:12 PM, sai krishnam raju potturi <
> pskraju88@gmail.com> wrote:
>
>>
>> hi;
>> We have cassandra cluster with Vnodes spanning across 3 data
>> centers. We take backup of the snapshots from one datacenter.
>> In a doomsday scenario, we want to restore a downed datacenter, with
>> snapshots from another datacenter. We have same number of nodes in each
>> datacenter.
>>
>> 1 : We know it requires copying the snapshots and their corresponding
>> token ranges to the nodes in new datacenter, and running nodetool
>> refresh.
>>
>> 2 : The question is, we will now have 2 datacenters, with the same exact
>> token ranges. Will that cause any problem.
>>
>> DC1 : Node-1 : token1......token10
>> Node-2 : token11 .....token20
>> Node-3 : token21 ..... token30
>> Node-4 : token31 ..... token40
>>
>> DC2 : Node-1 : token1.....token10
>> Node-2 : token11....token20
>> Node-3 : token21....token30
>> Node-4 : token31....token40
>>
>>
>> thanks
>> Sai
>>
>>
>>
>>
>
>
> --
> -----------------
> Nate McCall
> Austin, TX
> @zznate
>
> Co-Founder & Sr. Technical Consultant
> Apache Cassandra Consulting
> http://www.thelastpickle.com
>
Re: Re : Restoring nodes in a new datacenter, from snapshots in an
existing datacenter
Posted by Nate McCall <na...@thelastpickle.com>.
You cannot use the identical token ranges. You have to capture membership
information somewhere for each datacenter, and use that token information
when briging up the replacement DC.
You can find details on this process here:
http://docs.datastax.com/en/cassandra/2.0/cassandra/operations/ops_snapshot_restore_new_cluster.html
That process is straight forward, but it can go south pretty quickly if you
miss a step. It's a really good idea to set asside some time to try this
out in a staging/test system and build a runbook for the process targeting
your specific environment.
On Fri, Aug 28, 2015 at 1:12 PM, sai krishnam raju potturi <
pskraju88@gmail.com> wrote:
>
> hi;
> We have cassandra cluster with Vnodes spanning across 3 data centers.
> We take backup of the snapshots from one datacenter.
> In a doomsday scenario, we want to restore a downed datacenter, with
> snapshots from another datacenter. We have same number of nodes in each
> datacenter.
>
> 1 : We know it requires copying the snapshots and their corresponding
> token ranges to the nodes in new datacenter, and running nodetool refresh.
>
> 2 : The question is, we will now have 2 datacenters, with the same exact
> token ranges. Will that cause any problem.
>
> DC1 : Node-1 : token1......token10
> Node-2 : token11 .....token20
> Node-3 : token21 ..... token30
> Node-4 : token31 ..... token40
>
> DC2 : Node-1 : token1.....token10
> Node-2 : token11....token20
> Node-3 : token21....token30
> Node-4 : token31....token40
>
>
> thanks
> Sai
>
>
>
>
--
-----------------
Nate McCall
Austin, TX
@zznate
Co-Founder & Sr. Technical Consultant
Apache Cassandra Consulting
http://www.thelastpickle.com