authenticator | string

Default: PasswordAuthenticator

Authentication backend. Only PasswordAuthenticator and AllowAllAuthenticator are supported. You should only use AllowAllAuthenticator for legacy applications that cannot provide authentication credentials.

authorizer | string

Default: AllowAllAuthorizer

Authorization backend, implementing IAuthorizer; used to limit access/provide permissions Out of the box, Cassandra provides AllowAllAuthorizer & CassandraAuthorizer - AllowAllAuthorizer allows any action to any user - set it to disable authorization. - CassandraAuthorizer stores permissions in system_auth.permissions table.

backup_dir | string

Default: /srv/cassandra/backups

Location to store backups

backup_frequency | string

Default: daily

One of "daily" or "weekly"

backup_keep_count | int

Default: 7

How many backups to keep.

backup_tables | string

YAML-formatted list of tables (and fields) to back up. e.g. - airplanes (name, manufacturer, year, mach) - boats - cars.manufacturer

cluster_name | string

Default: juju

Name of the Cassandra cluster. This is mainly used to prevent machines in one logical cluster from joining another. All Cassandra services you wish to cluster together must have the same cluster_name. This setting cannot be changed after service deployment.

commitlog_directory | string

Default: commitlog

Commit log directory. The path is relative to /var/lib/cassandra or the block storage broker external mount point.

compaction_throughput_mb_per_sec | int

Default: 16

Throttles compaction to the given total throughput (in MB/sec) across the entire system. The faster you insert data, the faster you need to compact in order to keep the sstable count down, but in general, setting this to 16 to 32 times the rate you are inserting data is more than sufficient. Setting this to 0 disables throttling. Note that this account for all types of compaction, including validation compaction.

data_file_directories | string

Default: data

Space delimited data directories. Use multiple data directories to split data over multiple physical hardware drive partitions. Paths are relative to /var/lib/cassandra or the block storage broker external mount point.

datacenter | string

Default: juju

The node's datacenter used by the endpoint_snitch. e.g. "DC1". It cannot be changed after service deployment.

edition | string

Default: community

One of 'community', 'dse', or 'apache-snap'. 'community' uses the Apache Cassandra packages. 'dse' is for DataStax Enterprise. Selecting 'dse' overrides the jvm setting. 'apache-snap' uses a snap package of Apache Cassandra.

extra_packages | string

Extra packages to install. A space delimited list of packages.

heap_newsize | string

Default: 32M

The size of the JVM's young generation in the heap. If you set this, you should also set max_heap_size. If in doubt, go with 100M per physical CPU core. The default is automatically tuned.

http_proxy | string

Value for the http_proxy and https_proxy environment variables. This causes pip(1) and other tools to perform downloads via the proxy server. eg. http://squid.dc1.lan:8080

install_keys | string

Default: - null # Apache package signing key added automatically. - null # PPA package signing key added automatically. - null # PPA package signing key added automatically. # - null # DataStack package signing key added automatically.

charm-helpers standard listing of package install source signing keys, corresponding to install_sources.

install_sources | string

Default: - deb http://www.apache.org/dist/cassandra/debian 30x main - ppa:openjdk-r/ppa # For OpenJDK 8 - ppa:cassandra-charmers/stable # For Python driver # - deb http://debian.datastax.com/community stable main # DSE requires you to register and add your username/password here. # - deb http://un:pw@debian.datastax.com/enterprise stable main

charm-helpers standard listing of package install sources. If you are using Datastax Enterprise, you will need to override one defaults with your own username and password.

io_scheduler | string

Default: noop

Set kernel io scheduler for persistent storage. https://www.kernel.org/doc/Documentation/block/switching-sched.txt

jre | string

Default: openjdk

Which Java runtime environment to use. May be 'openjdk' or 'oracle'.

listen_interface | string

Network interface used for connecting to other Cassandra nodes. Must correspond to a single IP address. By default, the unit's public IP address is used.

max_heap_size | string

Default: 384M

Total size of Java memory heap, for example 1G or 512M. If you set this, you should also set heap_newsize. The default is automatically tuned.

nagios_context | string

Default: juju

Used by the nrpe subordinate charms. A string that will be prepended to instance name to set the host name in nagios. So for instance the hostname would be something like: juju-myservice-0 If you're running multiple environments with the same services in them this allows you to differentiate between them.

nagios_disk_crit_pct | int

Default: 25

The pct of data disk used to trigger a nagios critcal alert

nagios_disk_warn_pct | int

Default: 50

The pct of data disk used to trigger a nagios warning

nagios_heapchk_crit_pct | int

Default: 90

The pct of heap used to trigger a nagios critcal alert

nagios_heapchk_warn_pct | int

Default: 80

The pct of heap used to trigger a nagios warning

nagios_servicegroups | string

A comma-separated list of nagios servicegroups. If left empty, the nagios_context will be used as the servicegroup

native_transport_port | int

Default: 9042

Native protocol port for native protocol clients.

num_tokens | int

Default: 256

Number of tokens per node.

package_status | string

Default: install

The status of service-affecting packages will be set to this value in the dpkg database. Useful valid values are "install" and "hold".

partitioner | string

Default: Murmur3Partitioner

The cassandra partitioner to use. Use Murmur3Partitioner, unless another is required for backwards compatibility.

private_jre_url | string

URL for the private jre tar file. DSE requires Oracle Java SE 8 Server JRE (eg. server-jre-8u60-linux-x64.tar.gz).

rack | string

The rack used by the endpoint_snitch for all units in this service. e.g. "Rack1". This cannot be changed after deployment. It defaults to the service name. Cassandra will store replicated data in different racks whenever possible.

rpc_interface | string

Network interface used for client connections. Must correspond to a single IP address. By default, the unit's public IP address is used.

rpc_port | int

Default: 9160

Thrift protocol port for legacy clients.

saved_caches_directory | string

Default: saved_caches

Saved caches directory. The path is relative to /var/lib/cassandra or the block storage broker external mount point.

ssl_storage_port | int

Default: 7001

Cluster secure communication port. TODO: Unused. configure SSL.

storage_port | int

Default: 7000

Cluster communication port

stream_throughput_outbound_megabits_per_sec | int

Default: 200

Throttles all outbound streaming file transfers on nodes to the given total throughput in Mbps. This is necessary because Cassandra does mostly sequential IO when streaming data during bootstrap or repair, which can lead to saturating the network connection and degrading rpc performance. When unset, the default is 200 Mbps or 25 MB/s. 0 to disable throttling.

tombstone_failure_threshold | int

Default: 100000

When executing a scan, within or across a partition, we need to keep the tombstones seen in memory so we can return them to the coordinator, which will use them to make sure other replicas also know about the deleted rows. With workloads that generate a lot of tombstones, this can cause performance problems and even exaust the server heap. Adjust the thresholds here if you understand the dangers and want to scan more tombstones anyway.

tombstone_warn_threshold | int

Default: 1000

When executing a scan, within or across a partition, we need to keep the tombstones seen in memory so we can return them to the coordinator, which will use them to make sure other replicas also know about the deleted rows. With workloads that generate a lot of tombstones, this can cause performance problems and even exaust the server heap. Adjust the thresholds here if you understand the dangers and want to scan more tombstones anyway.

wait_for_storage_broker | boolean

Do not start the service before external storage has been mounted using the block storage broker relation. If you do not set this and you relate the service to the storage broker, then your service will have started up using local disk, and later torn down and rebuilt when the external storage became available.

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