Elasticsearch 7.10 : How to safely remove a node and free up space?

[Soumya_Ranjan_Sahoo]

As I am running out of my disk space, I want to remove all the indices from the node. Note that I have just one node, and I am running the elastic server on my local machine.

Basically, when I start the elastic server, it fails with the following log -

[2020-12-13T22:06:51,839][WARN ][o.e.c.r.a.DiskThresholdMonitor] [sedna] flood stage disk watermark [95%] exceeded on [k7t835EJQ6KzPu-7a-aW8Q][sedna][/home/ssahoo/elasticsearch-7.10.0/data/nodes/0] free: 879mb[0.8%], all indices on this node will be marked read-only

While on the terminal I get the following error -

   Could not rename log file 'logs/gc.log' to 'logs/gc.log.05' (Reserved).
(base) ssahoo@sedna:~/elasticsearch-7.10.0$ [2020-12-14T17:07:17,831][WARN ][stderr                   ] [sedna] Exception in thread "main" org.elasticsearch.bootstrap.BootstrapException: java.io.IOException: Input/output error
2020-12-14 17:07:17,848 main ERROR Unable to move file /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch_server.json to /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch-2020-12-13-1.json: java.nio.file.FileSystemException /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch_server.json -> /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch-2020-12-13-1.json: Disk quota exceeded
2020-12-14 17:07:17,852 main ERROR Unable to copy file /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch_server.json to /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch-2020-12-13-1.json: java.nio.file.FileSystemException /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch-2020-12-13-1.json: Disk quota exceeded
2020-12-14 17:07:17,857 main ERROR Unable to move file /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch.log to /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch-2020-12-13-1.log: java.nio.file.FileSystemException /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch.log -> /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch-2020-12-13-1.log: Disk quota exceeded
2020-12-14 17:07:17,861 main ERROR Unable to copy file /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch.log to /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch-2020-12-13-1.log: java.nio.file.FileSystemException /home/ssahoo/elasticsearch-7.10.0/logs/elasticsearch-2020-12-13-1.log: Disk quota exceeded
[2020-12-14T17:07:17,863][WARN ][stderr                   ] [sedna] Likely root cause: java.io.IOException: Input/output error
[2020-12-14T17:07:17,864][WARN ][stderr                   ] [sedna]     at java.base/java.io.FileDescriptor.close0(Native Method)
[2020-12-14T17:07:17,864][WARN ][stderr                   ] [sedna]     at java.base/java.io.FileDescriptor.close(FileDescriptor.java:297)

Therefore I want to free up space by removing all the indices, and therefore the node. So how can I remove the single node that I have?

Or if may I ask what would your suggestion be to overcome this? I can't afford additional disk space and is my major constraint.

Thank you.

[warkolm (Mark Walkom)]

Welcome to our community!

You can remove indicies from Elasticsearch by using the API as per https://www.elastic.co/guide/en/elasticsearch/reference/current/indices-delete-index.html.

[Soumya_Ranjan_Sahoo]

Thank you.

I have 2 follow up questions here -

1. How do I get to know the name of all the indices that are created?

2. I have created my indices using the following put request with the index name being bm25

requests.put('http://localhost:9200/bm25', data=json.dumps(settings), headers=headers) 

So, how do I delete an index (the above bm25, for instance) using python? Can you help me with an equivalent python syntax, please?

[warkolm (Mark Walkom)]

1. Look at the _cat/indices?v endpoint.
2. https://elasticsearch-py.readthedocs.io/en/v7.10.1/api.html?highlight=delete#elasticsearch.client.IndicesClient.delete looks like it.