deleting old indexes in amazon elasticsearch - amazon-web-services

Question

We are using AWS Elasticsearch for logs. The logs are streamed via Logstash continuously. What is the best way to periodically remove the old indexes?
I have searched and various approaches recommended are:
Use lambda to delete old indexes - https://medium.com/#egonbraun/periodically-cleaning-elasticsearch-indexes-using-aws-lambda-f8df0ebf4d9f
Use scheduled docker containers - http://www.tothenew.com/blog/running-curator-in-docker-container-to-remove-old-elasticsearch-indexes/
These approaches seem like an overkill for such a basic requirement as "delete indexes older than 15 days"
What is the best way to achieve that? Does AWS provide any setting that I can tweak?

Answer 1

Elasticsearch 6.6 brings a new technology called Index Lifecycle Manager See here. Each index is assigned a lifecycle policy, which governs how the index transitions through specific stages until they are deleted.
For example, if you are indexing metrics data from a fleet of ATMs into Elasticsearch, you might define a policy that says:
When the index reaches 50GB, roll over to a new index.
Move the old index into the warm stage, mark it read only, and shrink it down to a single shard.
After 7 days, move the index into the cold stage and move it to less expensive hardware.
Delete the index once the required 30 day retention period is reached.
The technology is in beta stage yet, however is probably the way to go from now on.

Answer 2

Running curator is pretty light and easy.
Here you can find a Dockerfile, config and action-file.
https://github.com/zakkg3/curator
Also, Curator can help you if you need to (among others):
Add or remove indices (or both!) from an alias
Change shard routing allocation
Delete snapshots
Open closed indices
forceMerge indices
reindex indices, including from remote clusters
Change the number of replicas per shard for indices
rollover indices
Take a snapshot (backup) of indices
Restore snapshots
https://www.elastic.co/guide/en/elasticsearch/client/curator/current/index.html
Here is a typical action file for delete indices older than 15 days:
actions:
1:
action: delete_indices
description: >-
Delete indices older than 15 days (based on index name), for logstash-
prefixed indices. Ignore the error if the filter does not result in an
actionable list of indices (ignore_empty_list) and exit cleanly.
options:
ignore_empty_list: True
disable_action: True
filters:
- filtertype: pattern
kind: prefix
value: logstash-
- filtertype: age
source: name
direction: older
timestring: '%Y.%m.%d'
unit: days
unit_count: 15

Answer 3

I followed the elasticsearch-curator documentation to install the package:
https://www.elastic.co/guide/en/elasticsearch/client/curator/current/pip.html
Then I used the AWS base example of how to automate the indexes cleanup using the signed based authentication provided by requests_aws4auth package:
https://docs.aws.amazon.com/elasticsearch-service/latest/developerguide/curator.html
It worked like a charm.
You can decide to run this inside a lambda, docker or include it in your own DevOps cli.