Database Reference
In-Depth Information
Cassandra logging settings. The only thing that one may want to change in this file is the
following line so that we can change the location where logs are located:
<fileNamePattern>${cassandra.logdir}/
system.log.%i.zip</fileNamePattern>
The
cassandra-topology.properties
file is to be filled with cluster-specific
values if you use
PropertyFileSnich
. We'll discuss more on this in the present
chapter, although we have an idea about it from
Chapter 2
,
Cassandra Architecture
.
The
cassandra.yaml
file and other files can be accessed from the
conf
directory un-
der the installation directory for a tarball installation. For repository installation, the
cas-
sandra.yaml
file and other files can be found under
/etc/cassandra
.
Setting up data and commitlog directories
As discussed earlier, one should configure the
data
and
commitlog
directories onto
separate disk drives to improve performance. The
cassandra.yaml
file holds all these
configurations and more.
Note
AWS EC2 users
Although it is recommended to have data and commit logs on two drives, for EC2 in-
stance store type servers, it is recommended to set up the RAID 0 configuration and use it
for both the
data
and
commitlog
directories. It performs better than having one of
those on the root device and other on ephemeral. Visit
https://aws.amazon.com/articles/
1074
to create the RAID 0 setup on EC2 instances.
EBS-backed instances are a bad choice for Cassandra installation owing to their slow I/O
performance and the same goes for any NAS setup.
To update data directories, edit the following lines in
cassandra.yaml
:
# directories where Cassandra should store data on disk.
data_file_directories: /var/lib/cassandra/data
