Regarding IGNITE_HOME/work/db folder - Snapshot and recovery

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Zaheer Zaheer
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Regarding IGNITE_HOME/work/db folder - Snapshot and recovery

Hi,

In this post it has been mentioned that to manually take a snapshot of
Ignite without using commercial solutions, we need to deactivate the cluster
, copy work/db folder to our backup location and activate cluster. And to
restore we deactivate, copy the backed up data and activate.

http://apache-ignite-users.70518.x6.nabble.com/Snapshot-backup-of-Ignite-native-persistance-data-tp20103.html

When I was trying this, I faced these errors :

1. WAL error : On restoring it says critical WAL archive missing and the
nodes crash.
2. Node Lock : This lock in node00-UUID folder is held from start to stop of
a node. So deactivating the cluster will not remove the lock.

I tried copying only the node00-UUID folders without WAL and I was able to
restore my caches. Is this approach correct ? Will WAL overwrite the
restored node00-UUID folders' data ?







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aealexsandrov aealexsandrov
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Re: Regarding IGNITE_HOME/work/db folder - Snapshot and recovery

Hi,

The error means that some of your data could be in inconsistency state
because of, for example, stopping of the node during the checkpoint process.

However, WAL and WAL archive can be required for cluster startup in some
cases because they contain the recovery information for cache data. You can
read it here:

https://apacheignite.readme.io/docs/write-ahead-log

I guess that you moved your data without moving of the WAL and/or WAL
archive. Note that in case if you don't set the paths to WAL and WAL_ARC
then Ignite will try to find them in IGNITE_HOME location.

As I see Ivan asked you to copy:

1){$IGNITE_HOME}\work\db
2){$IGNITE_HOME}\work\db\wal

But you said that you copied only work/db. Looks like without \work\db\wal
it can't be applied.

However, I suggest you to the backup the whole working directory that will
contain:

1){$IGNITE_HOME}\work\db
2){$IGNITE_HOME}\work\db\wal
3){$IGNITE_HOME}\work\binary_meta
4){$IGNITE_HOME}\work\marshaler

Last two will contain information about your classes.

BR,
Andrei



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ilya.kasnacheev ilya.kasnacheev
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Fwd: Regarding IGNITE_HOME/work/db folder - Snapshot and recovery

In reply to this post by Zaheer
Hello!

Actually I think that checkpoint is performed when cluster is deactivated, so db/ should be in consistent state after deactivation. This means nodes should startup OK after removal of all WAL, WAL Archive and WAL marker files.

Be sure to check that in development before going live with this solution, of course.

Regards,
--
Ilya Kasnacheev


пн, 3 июн. 2019 г. в 08:00, Zaheer <[hidden email]>:
Hi,

In this post it has been mentioned that to manually take a snapshot of
Ignite without using commercial solutions, we need to deactivate the cluster
, copy work/db folder to our backup location and activate cluster. And to
restore we deactivate, copy the backed up data and activate.

http://apache-ignite-users.70518.x6.nabble.com/Snapshot-backup-of-Ignite-native-persistance-data-tp20103.html

When I was trying this, I faced these errors :

1. WAL error : On restoring it says critical WAL archive missing and the
nodes crash.
2. Node Lock : This lock in node00-UUID folder is held from start to stop of
a node. So deactivating the cluster will not remove the lock.

I tried copying only the node00-UUID folders without WAL and I was able to
restore my caches. Is this approach correct ? Will WAL overwrite the
restored node00-UUID folders' data ?







--
Sent from: http://apache-ignite-users.70518.x6.nabble.com/
Zaheer Zaheer
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Re: Fwd: Regarding IGNITE_HOME/work/db folder - Snapshot and recovery

Zaheer Zaheer
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Re: Regarding IGNITE_HOME/work/db folder - Snapshot and recovery

In reply to this post by aealexsandrov
Thank you Andrei



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