Support Forums : DataStax

DataStax Support Forums » OpsCenter

Technical question about OpsCenter

(2 posts) (2 voices)

Started 1 year ago by blueplastic
Latest reply from nickmbailey
This topic is not resolved

Tags:

blueplastic
Member

I have a question about some of the details of OpsCenter's Column Family in Cassandra.

We are working on building a recyclable demo of Cassandra in Amazon using custom AMIs and EBS volumes. I have a question about whether OpsCenter can be installed permanently into the AMIs or whether we would have to reinstall it each time we respawn the cluster (with different IPs) using the AMIs.

Say I have 5 Amazon EC2 nodes running Brisk 1.0 and the first node has OpsCenter installed on it. The Cassandra database (including the OpsCenter CF) is not on the local ephemeral drives, but rather on EBS volumes that were connected to the 5 nodes.

Then I permanently store each node as an AMI that I can relaunch later to respawn the cluster. So, typically we will terminate the 5 nodes, but keep the databases intact on the 5 EBS volumes. When we want to show a demo of Cassandra, we'll launch 5 new EC2 nodes (from 5 individualized AMIs) and reconnect the 5 EBS volumes to the new EC2 nodes. Note that the IP addresses for the new 5 nodes will be different than the old five nodes. We have some puppet scripts that will update the YAML file and other configuration files on the fresh 5 nodes before starting Cassandra.

Casssandra restarts fine and reconnects to all of the databases on the EBS drive. But my question is regarding OpsCenter.

When OpsCenter is first installed, it detects the Amazon Private IPs for all 5 nodes and installs Agents on them and creates a special OpsCenter Column Family to store metrics.

My question is: In our recyclable demo, can we install OpsCenter on the first node and the agents on the rest of the nodes BEFORE saving our permanent AMIs? Are the private IPs for the cluster stored that OpsCenter Column family so that it would get confused/break if the cluster started up with different IPs?

Currently, we don't have OpsCenter on the AMIs. Instead every time we launch a fresh 5 nodes, we reinstall OpsCenter and the Agents.

We would like to automate this and make the respawn process faster by just baking OpsCenter into the AMI so even if we relaunch the cluster with new private IPs, we don't have to reinstall OpsCenter.

Is it possible to do what we want to do?

- Sameer

Posted 1 year ago #
nickmbailey
Key Master

It would be possible to bundle the agent into the ami.

The agent needs 3 things in order to work with opscenter: The ip for opscenter, the agent's own ip, and the correct ssl files.

The ip for opscenter and the agent ip are located in a config file at '/var/lib/opscenter-agent/conf/address.yaml'. You will need to configure those properties correctly when the new ec2 server boots up.

The ssl files that opscenter uses are generated when the main opscenter package is installed, and are lcoated in /var/lib/opscenter/ssl/. The correct files for the agent are then installed at /var/lib/opscenter-agent/ssl on the agent machines. You can use the same set of files between installations if you wish. So if you configure your machines to always use the same ssl files and configure the ips in address.yaml you should be able to do something like this.

Posted 1 year ago #

RSS feed for this topic

Reply

You must log in to post.