Re: warm-standby errors

  > Right now, Warm Standby has same functionality as equivalent Oracle
> feature - i.e. no way to confirm absence of corruption. However, WAL
> records contain CRC checks that ensure the transferred data is correct,
> which is more than most other replication techniques posess. Hot Standby
> will allow access to data blocks to allow them to be read and checked,
> though that is also possible with an external utility to some extent.

Do you have a link to documentation on how to do this?

> It probably isn't practical with any replication system to confirm the
> exact contents of both nodes while replication is running at reasonable
> speed. Some heuristics may be possible.

agreed

>
> Do you have anything in mind, other than "detect corruption"?

Really what I am after, is being able to say 'yes our replication is as
error-free as it can be' with the most amount of certainty as possible.

>> How can I prevent this
>> error from occurring ?
>
> You haven't shown us the error, just what happens afterwards.

I might have written too fast. I am curious to know what causes the
message to appear in the logs. It only appears when a instance is
shutdown and then restarted again. Is there some thing I can do so that
the statement isn't triggered when I restart the warm-standby instance?
could it be a setting that I have missed?

For reference, here is the head of the 2 log files created when the
instance was restarted

$ ggrep -A 1 -B 1 HINT *
edb-2009-04-07_012241.log-2009-04-07 01:22:41.361 GMT,,,,1750,,,1, //
LOG:  database system was interrupted while in recovery at log time
2009-04-02 17:04:54 GMT
edb-2009-04-07_012241.log:2009-04-07 01:22:41.361 GMT,,,,1750,,,2, //
HINT:  If this has occurred more than once some data may be corrupted
and you may need to choose an earlier recovery target.
edb-2009-04-07_012241.log-2009-04-07 01:22:41.362 GMT,,,,1750,,,3, //
LOG:  starting archive recovery
--
edb-2009-04-07_013609.log-2009-04-07 01:36:09.424 GMT,,,,1920,,,1, //
LOG:  database system was interrupted while in recovery at log time
2009-04-02 17:04:54 GMT
edb-2009-04-07_013609.log:2009-04-07 01:36:09.424 GMT,,,,1920,,,2, //
HINT:  If this has occurred more than once some data may be corrupted
and you may need to choose an earlier recovery target.
edb-2009-04-07_013609.log-2009-04-07 01:36:09.424 GMT,,,,1920,,,3, //
LOG:  starting archive recovery
--
edb-2009-04-27_071121.log-2009-04-27 07:11:21.213 GMT,,,,8261,,,1, //
LOG:  database system was interrupted while in recovery at log time
2009-04-27 06:55:08 GMT
edb-2009-04-27_071121.log:2009-04-27 07:11:21.213 GMT,,,,8261,,,2, //
HINT:  If this has occurred more than once some data may be corrupted
and you may need to choose an earlier recovery target.
edb-2009-04-27_071121.log-2009-04-27 07:11:21.213 GMT,,,,8261,,,3, //
LOG:  starting archive recovery
--
edb-2009-04-27_071747.log-2009-04-27 07:17:47.819 GMT,,,,8328,,,1, //
LOG:  database system was interrupted while in recovery at log time
2009-04-27 06:55:08 GMT
edb-2009-04-27_071747.log:2009-04-27 07:17:47.819 GMT,,,,8328,,,2, //
HINT:  If this has occurred more than once some data may be corrupted
and you may need to choose an earlier recovery target.
edb-2009-04-27_071747.log-2009-04-27 07:17:47.819 GMT,,,,8328,,,3, //
LOG:  starting archive recovery





Thanks,
  -Said