Re: Corrupted Data ? - Mailing list pgsql-general

On 08/08/2016 09:47 AM, Ioana Danes wrote:
>
>
> On Mon, Aug 8, 2016 at 12:37 PM, Adrian Klaver
> <adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>> wrote:
>
>     On 08/08/2016 09:28 AM, Ioana Danes wrote:
>
>
>
>         On Mon, Aug 8, 2016 at 12:19 PM, Adrian Klaver
>         <adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>
>         <mailto:adrian.klaver@aklaver.com
>         <mailto:adrian.klaver@aklaver.com>>> wrote:
>
>             On 08/08/2016 09:11 AM, Ioana Danes wrote:
>
>                 Hi,
>
>                 I suspect I am having a case of data corruption. Here
>         are the
>                 details:
>
>                 I am running postgres 9.4.8:
>
>                 postgresql94-9.4.8-1PGDG.rhel7.x86_64
>                 postgresql94-contrib-9.4.8-1PGDG.rhel7.x86_64
>                 postgresql94-libs-9.4.8-1PGDG.rhel7.x86_64
>                 postgresql94-server-9.4.8-1PGDG.rhel7.x86_64
>
>                 on CentOS Linux release 7.2.1511 (Core)
>
>                 This is happening in a production environment but
>         luckily on the
>                 reporting database.
>                 I have a cluster of 3 databases, db1 and db2 are masters and
>                 replicate
>                 between each other and also replicate to db3 (db1 <->
>         db2, db1
>                 -> db3,
>                 db2 -> db3).
>                 For replication I am using Bucardo.
>
>
>             I would say this is more a question for the Burcardo list:
>
>             https://mail.endcrypt.com/mailman/listinfo/bucardo-general
>         <https://mail.endcrypt.com/mailman/listinfo/bucardo-general>
>             <https://mail.endcrypt.com/mailman/listinfo/bucardo-general
>         <https://mail.endcrypt.com/mailman/listinfo/bucardo-general>>
>
>             I am just not seeing that replicating two masters on to a single
>             database is going to end well.
>
>
>         Only one master is active at one time the other one is in stand
>         by that
>         is a topic for another discussion but in our case that works well.
>
>         That was my first assumption, that it is a kind of a race
>         condition or a
>         bug on replication but I quickly ruled that out because that
>         does not
>         explain why when I filtered the table by transactionid = 75315815 it
>         shows one record with transactionid 75315811...
>
>         select gameplayid, transactionid, encodedplay from
>         abrazo.matchgameplay
>         where transactionid in (75315815) order by transactionid;;
>          gameplayid | transactionid | encodedplay
>         ------------+---------------+--------------
>           160019271 |      75315815 | mix:9,0,9
>           160019269 |      75315815 | mix:9,8,9
>           160019267 |      75315815 | mix:9,2,2
>           160019265 |      75315815 | mix:2,2,8
>           160019263 |      *75315811 *| backup:1,9,1
>           160019261 |      75315815 | backup:2,0,9
>
>         So I don't think it is a replication issue...
>
>
>     Other that, if I am following correctly, it is on the database(db3)
>     being replicated to. The only way db3 is getting its data is through
>     replication, is that correct?. On the master databases the data is
>     correct.
>
> OK, let's assume that what you're saying is correct and the replication
> has a bug, or corruption or whatever that is and the record gets created
> with transactionid = 75315811. Bucardo replication is trigger based and
> it is using a copy command to insert the new records into the replicated
> database.
>
> Then how can I explain that my query select gameplayid, transactionid,
> encodedplay from abrazo.matchgameplay where transactionid in (75315815)
> order by transactionid; returns me a record with transactionid 75315811???

Corrupted index on db3?

Might want to look in the db3 logs to see if anything pops out.

I just do not know enough about Burcardo to be of much help beyond that.

>
> Thanks,
> ioana
>
>
>
>     --
>     Adrian Klaver
>     adrian.klaver@aklaver.com <mailto:adrian.klaver@aklaver.com>
>
>


--
Adrian Klaver
adrian.klaver@aklaver.com