Database Reference
In-Depth Information
max is 1177812992
DEBUG 09:41:56,035 attempting to connect to lucky/192.168.1.2
DEBUG 09:41:57,025 Disseminating load info ...
This allows you to see exactly what Cassandra is doing and when, which is very helpful in
troubleshooting. But it's also helpful in simply understanding what Cassandra does to maintain
itself.
If you want to change the location of the logs directory, just find the following entry in the same
log4j.properties file and chose a different filename:
log4j.appender.R.File=/var/log/cassandra/system.log
There's not a different entry for Windows; on Windows systems this will automatically resolve
to C:\\var\log\cassandra\system.log.
NOTE
If you don't see any logfiles in this location, make sure that you are the owner of the directories, or at
least that proper read and write permissions are set. Cassandra won't tell you if it can't write the log; it
just won't. Same for the datafiles.
Note that this is the location for the log of the activity of the database, and not for Cassandra's
internal datafiles. Those are stored in /var/lib/cassandra.
Tailing
You don't need to start Cassandra using the foreground switch in order to see the rolling log.
You can also simply start it without the
-f
option and then tail the logs. Tailing is not specific
to Cassandra; it's a small program available in Linux distributions to see new values printed to a
console as they are appended to a file.
To tail the logs, start Cassandra like this:
>bin/cassandra
Then open a second console, enter the
tail
command, and pass it the location of the particular
file you want to tail, like this:
>tail -f /var/log/cassandra/system.log
The
-f
option means “follow,” and as Cassandra outputs information to the physical logfile,
tail
will output it to the screen. To stop tailing, just type Ctrl-C.
