rollastic 0.0.5

Automated ElasticSearch cluster rolling restarts/upgrades via SaltStack

Rollastic
=========

Elasticsearch cluster management, namely rolling restart and upgrades.
Your cluster should be deployed/managed via SaltStack; this is meant to be ran on your Salt master.

While currently not a *hard* requirement (as far as states applied on an upgrade, a highstate is performed), we
recommend to use our fork of the elasticsearch Salt formula: https://github.com/vkgit/saltstack-elasticsearch-formula,
as further integration will happen in the future.


Install
-------

```
pip install rollastic
```

Usage
-----

### Restart

This currently requires Salt to restart the service after shutting it down.

```
Usage: rollastic restart [OPTIONS] MASTER_NODE

Rolling restart of cluster.

MASTER_NODE is the initial node to query to get the list of master nodes
to connect to. Rollastic will connect to all master nodes to avoid relying
on one to be up for the roll procedure.

This will:
- Collect and order the nodes to roll.
If you opted to include master nodes, they are always done first.
- Wait until cluster is in green health
- For each node from #1 above
If node's heap used percentage is over kill-at-heap:
* Disable cluster allocation
* Ping node through Salt to verify connectivity
* Shutdown node through ES API
* Wait for ES to die for 2m.
If it's not dead, run a killall java and wait another 2m.
If it's still not dead, fail.
* Start elasticsearch service through Salt
* Wait until node joins cluster with an uptime within 120s.
* Enable allocation
* Wait until cluster is in green health

Options:
--masters / --no-masters Restart master nodes as well [false]
--datas / --no-datas Restart data nodes [true]
--kill-at-heap INTEGER Heap used percentage threshold to restart that
node [85]
--help Show this message and exit.
```

### Upgrade

This works hand in hand with our fork of the elasticsearch Salt formula: https://github.com/vkgit/saltstack-elasticsearch-formula

```
Usage: rollastic upgrade [OPTIONS] MASTER_NODE

Rolling upgrade of cluster.

MASTER_NODE is the initial node to query to get the list of master nodes
to connect to. Rollastic will connect to all master nodes to avoid relying
on one to be up for the roll procedure.

This will:
- Collect and order the nodes to roll.
If you opted to include master nodes, they are always done first.
- Wait until cluster is in green health
- For each node from #1 above
If node's ES version is under minimum_version:
* Disable cluster allocation
* Ping node through Salt to verify connectivity
* Run a Salt highstate
* Check for an available upgrade on the Elasticsearch package, if so:
- Shutdown node through ES API
- Wait for ES to die for 2m.
If it's not dead, run a killall java and wait another 2m.
If it's still not dead, fail.
* If ES was stopped at any point in this:
- Start elasticsearch service if it's not already started
- Wait until node joins cluster with an uptime within 120s.
* Enable allocation
* Wait until cluster is in green health

Options:
--masters / --no-masters Restart master nodes as well [false]
--datas / --no-datas Restart data nodes [true]
--minimum-version TEXT Minimum version to upgrade to [1.7.1]
--help Show this message and exit.
```