Forum: Managing VoltDB

Post: With Durability, no data after restart

With Durability, no data after restart
Sabrina
Apr 5, 2014
Hello,

I'm using Enterprise Edition VoltDB 4.0.2.3 and my deployment.xml looks like this:
<?xml version="1.0" ?>
<deployment>
<cluster hostcount="1" sitesperhost="3" kfactor="0"/>
<commandlog enabled="true" > <frequency transactions="1000" /></commandlog>
<paths>
<commandlog path="/Platte/voltdblog/" />
<commandlogsnapshot path="/Platte/voltdb/cmdsnaps/" />
</paths>
<httpd enabled="true">
<jsonapi enabled="true" />
</httpd>
</deployment>

I insert ~900.000 Data items in the database, but when I restart the server, the tables are zero. What is wrong in my configuration? I thoght that every 1000 transactions the transaction is saved on disk.

Thanks.

Sabrina
scooper
Apr 5, 2014
Hi Sabrina,

What command are you using to restart the server?

Since command logging is enabled the "recover" command is the one that handles replaying the previous sessions's command log into the new session.

http://voltdb.com/docs/UsingVoltDB/RunRestart.php

Cheers,
Steve
Sabrina
Apr 5, 2014
Hi Steve,

great - the problem was the start command. Now it works fine!
How often does VoltDB create a snapshot, when there is nothing configured (like my deployment.xml file).

Thanks,
Sabrina
scooper
Apr 6, 2014
Hi Sabrina,

Snapshots are only taken upon user request, e.g. using "voltadmin save", unless you configure automatic snapshots in deployment.xml.

http://voltdb.com/docs/UsingVoltDB/SaveSnapshotAuto.php

Cheers,
Steve
rmorgenstein
Apr 6, 2014
In addition to the snapshots that Steve described, there are also command log truncation snapshots that happen automatically. See https://voltdb.com/docs/UsingVoltDB/ChapCmdLog.php for more information about what they do and how to configure them.

Ruth