Riak is a high performance, distributed key/value data store released by Basho.
The module is designed with production systems in mind and aims to fully automate the deployment of a Riak cluster and tune your systems for optimal performance.
This module deploys a Riak cluster on Red Hat distributions. It's designed to automate the setup of an entire cluster and should be applied to multiple hosts. It will handle the operations necessary to create the cluster, including plan, commit and join. The module uses your existing yum repos to install Riak and Erlang and Linux will be tuned for performance as recommended by Basho.
The module has been tested on RHEL/CentOS 6.4 using riak-1.4.8 and erlang-rebar-2.1.0. Compatible with Puppet 2.7 or higher.
The class parameter cluster_join_node defines the host that all members of the cluster will join. All hosts that join this node will automatically be members of the same cluster.
To avoid external dependencies this module is designed to use your existing yum repos, therefore ensure you have the following packages available:
- riak-1.4.8
- erlang-rebar-2.1.0
Working name resolution is required. Ensure that each host can resolve itself and the host that's specified by the cluster_join_node parameter.
These packages will be Installed:
- riak-1.4.8
- erlang-rebar-2.1.0
Performance optimizations are made as recommended by Basho:
- Sets Linux kernel parameters and tunes ulimits as required
- Swap disk is disabled
- Filesystem mount options are added to improve I/O
- The Linux I/O scheduler (elevator) is changed from CFQ to Deadline for the 3 first serial block devices detected, e.g. /dev/sda, /dev/sdb and /dev/sdc.
To create a 5 node cluster with a ring size of 256 where all nodes join riak01.domain.local:
While not strictly necessary, you may want to provision Riak on riak01.domain.local before the other nodes so it will be ready to accept members as they join the cluster.
Create a node definition like so:
node /^riak0[1-5]\.domain\.local$/ {
class { 'riak':
cluster_join_node => 'riak01.domain.local',
ring_creation_size => '256',
}
}
cluster_join_node
required: yes
The node to join when creating the cluster. All nodes that you wish to make into a cluster should use the same value for this. The system you select is arbitrary and can be any host that will become part of the cluster.
Set max file handles via sysctl and ulimits
sysctl_fs_file_max
default: 65536
ulimits_nofile_soft
default: 16000
ulimits_nofile_hard
default: 20000
ring_creation_size
default: 128
The number of partitions that make up your Riak cluster. Must be a multiple of 2. Check cluster capacity planning docs for details.
riak_api_pb_backlog
default: 64
Maximum length to which the queue of pending connections may grow.
riak_search
default: false
To enable Search functionality set this 'true'. Not recommended on production systems.
riak_sysmon_process_limit
default: 30
Sysmon process limit.
riak_control_enabled
default: false
Whether to enable the Riak control GUI
riak_control_username
default: admin
Username for Riak control
riak_control_password`
default: pass
Password for Riak control
- Multiple Puppet runs may be necessary to bring all nodes into the cluster. If you ensure Riak has been provisioned on the host cited by
cluster_join_nodebefore the other nodes, the cluster join operations should work on one Puppet run. - The Linux I/O scheduler is only tuned on the 3 first serial block devices detected. Needs to be generalized.
- Only tested on RHEL 6 distros so far
Visit the repo on Github
Pete Cornell / @9Dreamer / https://github.com/Cornellio