Leveraging Opscenter to make Cassandra Easy

Full disclosure about me

• I work for Datastax, but this is not an official Datastax talk
• I've talked about tons of different frameworks and libraries over the years without being a sales pitch
• I do think opscenter is pretty awesome

What is Opscenter?

• Provisioning tool
• Monitoring and Alerting tool
• Simplifies many cassandra operations
• Works with both DSE and DSC (although some features are DSE only)
• Swiss army knife for Ops teams

How to get started?

• Part of datastax Sandbox http://www.datastax.com/download#dl-sandbox
• Tarball install http://www.datastax.com/download#dl-opscenter
• Package install (yum/apt-get)
• Once running goto http://localhost:8888/ (or whatever your hostname is)

Manage Existing Cluster

• Possible to provision new as well, but most people trying this will probably have a cluster
• Pick a cassandra node to connect to (same criteria as a seed node)
• If using non-standard rpc/thrift ports, specify them.

Depending on your cluster configuration, you may need to extend the timeout:

[clusters]
add_cluster_timeout = 30

Agents?

• Right now we have basic ring topology
• To get detailed information we need to install agents
• The Fix link at the top of the screen will install agents for us
• Agents have a small memory and cpu footprint, they are installed on each cassandra node and communicate with that node via JMX
• Much of the heavy lifting is pushed to the Opscenter server

The High Level

Trouble shooting Installation

• Opscenter to cassandra? cqlsh host port
• Opscenter to agent? curl -i host:61621/alive
• Agent to cassandra? jconsole/jmxterm/etc
• Agent/Opsc Stomp? (check logs)
• Set logging to debug http://www.datastax.com/documentation/opscenter/5.0/opsc/configure/opscConfigLogging.html
• Check permissions
• Bounce Opscenterd

Node Operations

• These are the kinds of operations you can also accomplish using nodetool
• Select a node from the ring view to bring up details, then issue an action
• In DSE it is possible to have a bulk action (although we document our API and you could script your own)
• (api docs https://www.datastax.com/documentation/opscenter/5.0/api/docs/index.html)

Cluster Operations

• Cassandra Config!
• Add nodes
• Restart
• Rebalance
• https://gist.github.com/philipsdoctor/5a34dfcfd1fe1f5c6d39

Monitoring

• Create custom dashboards
• Add graphs
• DSE allows user specific graphs

DSE Only

• Best Practice Services
• Backup/Restore
• Repair 
• Repair reading 
• http://www.datastax.com/documentation/opscenter/5.0/opsc/online_help/services/repairServiceErrors.html
• http://www.datastax.com/documentation/opscenter/5.0/opsc/online_help/services/repairServiceHowItWorks.html

Reading

• Opscenter docs http://www.datastax.com/documentation/opscenter/5.0/opsc/about_c.html
• Ports http://www.datastax.com/documentation/opscenter/5.0/opsc/reference/opscPorts_r.html
• Advanced Config
• http://www.datastax.com/documentation/opscenter/5.0/opsc/configure/opscConfigProps_r.html