Re: full and incremental repair consistency

[Jérôme Mainaud]

> - Either way, with or without the flag will actually be equivalent when
> none of the sstables are marked as repaired (this will change after the
> first inc repair).
>

So, if I well understand, the repair -full -local command resets the flag
of sstables previously repaired. So even if I had some sstable already
flagged, they won't be any more.

- The actual data component is mutable, only a flag in the STATS sstable
> component is mutated.
>

This is an important property I missed. That means that snapshots are
succeptible to mutate as they are hard links of actual file.
I also must care of this if I try to deduplicate files in a external backup
system.

Re: full and incremental repair consistency

[Paulo Motta]

When you say "you need to run a full repair without the -local flag", do
you mean I have to set the -full flag ? Or do you mean that the next repair
without arguments will be a full one because sstables or not flagged ?

- Either way, with or without the flag will actually be equivalent when
none of the sstables are marked as repaired (this will change after the
first inc repair).

By the way, I suppose the repair flag don't break sstable file
immutability, so I wonder how it is stored.

- The actual data component is mutable, only a flag in the STATS sstable
component is mutated.

2016-08-19 12:17 GMT-03:00 Jérôme Mainaud :

> It makes sense.
>
> When you say "you need to run a full repair without the -local flag", do
> you mean I have to set the -full flag ? Or do you mean that the next repair
> without arguments will be a full one because sstables or not flagged ?
>
> By the way, I suppose the repair flag don't break sstable file
> immutability, so I wonder how it is stored.
>
> --
> Jérôme Mainaud
> jer...@mainaud.com
>
> 2016-08-19 15:02 GMT+02:00 Paulo Motta :
>
>> Running repair with -local flag does not mark sstables as repaired, since
>> you can't guarantee data in other DCs are repaired. In order to support
>> incremental repair, you need to run a full repair without the -local flag,
>> and then in the next time you run repair, previously repaired sstables are
>> skipped.
>>
>> 2016-08-19 9:55 GMT-03:00 Jérôme Mainaud :
>>
>>> Hello,
>>>
>>> I have a 2.2.6 Cassandra cluster with two DC of 15 nodes each.
>>> A continuous incremental repair process deal with anti-entropy concern.
>>>
>>> Due to some untraced operation by someone, we choose to do a full repair
>>> on one DC with the command : nodetool repair --full -local -j 4
>>>
>>> Daily incremental repair was disabled during this operation
>>>
>>> The significant amount of stream session produced by this repair session
>>> confirms to me that it was a good necessary.
>>>
>>> However, I wonder if the sstables involved in that repair are flagged or
>>> if the next daily incremental repair will be equivalent to a full repair.
>>>
>>> I didn't use the -pr option since -pr and -local are actually mutually
>>> exclusive (whether they should is the subject of another thread). I chose
>>> -local because the link between the datacenter is slow. But maybe choosing
>>> -pr would have been a better choice.
>>>
>>> Is there a better way I should have handled this ?
>>>
>>> Thank you,
>>>
>>> --
>>> Jérôme Mainaud
>>> jer...@mainaud.com
>>>
>>
>>
>

Re: full and incremental repair consistency

[Jérôme Mainaud]

It makes sense.

When you say "you need to run a full repair without the -local flag", do
you mean I have to set the -full flag ? Or do you mean that the next repair
without arguments will be a full one because sstables or not flagged ?

By the way, I suppose the repair flag don't break sstable file
immutability, so I wonder how it is stored.

-- 
Jérôme Mainaud
jer...@mainaud.com

2016-08-19 15:02 GMT+02:00 Paulo Motta :

> Running repair with -local flag does not mark sstables as repaired, since
> you can't guarantee data in other DCs are repaired. In order to support
> incremental repair, you need to run a full repair without the -local flag,
> and then in the next time you run repair, previously repaired sstables are
> skipped.
>
> 2016-08-19 9:55 GMT-03:00 Jérôme Mainaud :
>
>> Hello,
>>
>> I have a 2.2.6 Cassandra cluster with two DC of 15 nodes each.
>> A continuous incremental repair process deal with anti-entropy concern.
>>
>> Due to some untraced operation by someone, we choose to do a full repair
>> on one DC with the command : nodetool repair --full -local -j 4
>>
>> Daily incremental repair was disabled during this operation
>>
>> The significant amount of stream session produced by this repair session
>> confirms to me that it was a good necessary.
>>
>> However, I wonder if the sstables involved in that repair are flagged or
>> if the next daily incremental repair will be equivalent to a full repair.
>>
>> I didn't use the -pr option since -pr and -local are actually mutually
>> exclusive (whether they should is the subject of another thread). I chose
>> -local because the link between the datacenter is slow. But maybe choosing
>> -pr would have been a better choice.
>>
>> Is there a better way I should have handled this ?
>>
>> Thank you,
>>
>> --
>> Jérôme Mainaud
>> jer...@mainaud.com
>>
>
>

Re: full and incremental repair consistency

[Paulo Motta]

Running repair with -local flag does not mark sstables as repaired, since
you can't guarantee data in other DCs are repaired. In order to support
incremental repair, you need to run a full repair without the -local flag,
and then in the next time you run repair, previously repaired sstables are
skipped.

2016-08-19 9:55 GMT-03:00 Jérôme Mainaud :

> Hello,
>
> I have a 2.2.6 Cassandra cluster with two DC of 15 nodes each.
> A continuous incremental repair process deal with anti-entropy concern.
>
> Due to some untraced operation by someone, we choose to do a full repair
> on one DC with the command : nodetool repair --full -local -j 4
>
> Daily incremental repair was disabled during this operation
>
> The significant amount of stream session produced by this repair session
> confirms to me that it was a good necessary.
>
> However, I wonder if the sstables involved in that repair are flagged or
> if the next daily incremental repair will be equivalent to a full repair.
>
> I didn't use the -pr option since -pr and -local are actually mutually
> exclusive (whether they should is the subject of another thread). I chose
> -local because the link between the datacenter is slow. But maybe choosing
> -pr would have been a better choice.
>
> Is there a better way I should have handled this ?
>
> Thank you,
>
> --
> Jérôme Mainaud
> jer...@mainaud.com
>