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Posted to user@cassandra.apache.org by john xie <sh...@gmail.com> on 2010/08/02 15:11:45 UTC

how to recover cassandra data

ReplicationFactor = 3

one day i stop 192.168.1.147 and remove cassandra data by mistake, can i
recover  192.168.1.147's cassadra data by restart cassandra ?



   <DataFileDirectories>
        <DataFileDirectory>/data1/cassandra/</DataFileDirectory>
        <DataFileDirectory>/data2/cassandra/</DataFileDirectory>
        <DataFileDirectory>/data3/cassandra/</DataFileDirectory>
    </DataFileDirectories>

/data3  mount  /dev/sdd

i remove /data3 and  formatt /dev/sdd


Address       Status     Load          Range
     Ring

135438270110006521520577363629178401179
192.168.1.148 Up         50.38 GB
 52435029392953385124849742453833332898     |<--|
192.168.1.145 Up         48.38 GB
 63161078970569359253391371326773726097     |   |
192.168.1.147 ?          23.5 GB
79546317728707787532885001681404757282     |   |
192.168.1.146 Up         26.34 GB
 135438270110006521520577363629178401179    |-->|

Re: how to recover cassandra data

Posted by Jonathan Shook <js...@gmail.com>.

Don't forget about the tombstones. (delete markers)
They are still present on the other two nodes, then they will
replicate to the 3rd node and finish off your deleted data.

On Mon, Aug 2, 2010 at 9:30 AM, Edward Capriolo <ed...@gmail.com> wrote:
> On Mon, Aug 2, 2010 at 9:11 AM, john xie <sh...@gmail.com> wrote:
>> ReplicationFactor = 3
>> one day i stop 192.168.1.147 and remove cassandra data by mistake, can i
>> recover  192.168.1.147's cassadra data by restart cassandra ?
>>
>>
>>    <DataFileDirectories>
>>         <DataFileDirectory>/data1/cassandra/</DataFileDirectory>
>>         <DataFileDirectory>/data2/cassandra/</DataFileDirectory>
>>         <DataFileDirectory>/data3/cassandra/</DataFileDirectory>
>>     </DataFileDirectories>
>> /data3  mount  /dev/sdd
>> i remove /data3 and  formatt /dev/sdd
>>
>> Address       Status     Load          Range
>>      Ring
>>
>> 135438270110006521520577363629178401179
>> 192.168.1.148 Up         50.38 GB
>>  52435029392953385124849742453833332898     |<--|
>> 192.168.1.145 Up         48.38 GB
>>  63161078970569359253391371326773726097     |   |
>> 192.168.1.147 ?          23.5 GB
>> 79546317728707787532885001681404757282     |   |
>> 192.168.1.146 Up         26.34 GB
>>  135438270110006521520577363629178401179    |-->|
>>
>>
>>
>>
>>
>>
>
> Since you have a replication factor of three if you bring a new node
> through auto-bootstrap data will migrate back to it since it has two
> copies. Nothing is lost.
>

Re: how to recover cassandra data

Posted by Edward Capriolo <ed...@gmail.com>.

On Mon, Aug 2, 2010 at 9:11 AM, john xie <sh...@gmail.com> wrote:
> ReplicationFactor = 3
> one day i stop 192.168.1.147 and remove cassandra data by mistake, can i
> recover  192.168.1.147's cassadra data by restart cassandra ?
>
>
>    <DataFileDirectories>
>         <DataFileDirectory>/data1/cassandra/</DataFileDirectory>
>         <DataFileDirectory>/data2/cassandra/</DataFileDirectory>
>         <DataFileDirectory>/data3/cassandra/</DataFileDirectory>
>     </DataFileDirectories>
> /data3  mount  /dev/sdd
> i remove /data3 and  formatt /dev/sdd
>
> Address       Status     Load          Range
>      Ring
>
> 135438270110006521520577363629178401179
> 192.168.1.148 Up         50.38 GB
>  52435029392953385124849742453833332898     |<--|
> 192.168.1.145 Up         48.38 GB
>  63161078970569359253391371326773726097     |   |
> 192.168.1.147 ?          23.5 GB
> 79546317728707787532885001681404757282     |   |
> 192.168.1.146 Up         26.34 GB
>  135438270110006521520577363629178401179    |-->|
>
>
>
>
>
>

Since you have a replication factor of three if you bring a new node
through auto-bootstrap data will migrate back to it since it has two
copies. Nothing is lost.