# Cluster locks up if master node filesystem becomes read-only

**URL:** https://discuss.elastic.co/t/cluster-locks-up-if-master-node-filesystem-becomes-read-only/38245
**Category:** Elasticsearch
**Created:** [January 1, 2016, 3:29pm UTC](https://discuss.elastic.co/t/cluster-locks-up-if-master-node-filesystem-becomes-read-only/38245 "2016-01-01T15:29:21Z")
**Posts on this page:** 1
**Showing post:** 3

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### Author: ![jprante](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/jprante/32/44941_2.png) [@jprante](https://discuss.elastic.co/u/jprante)
#### Post date: [January 2, 2016, 12:51am UTC](https://discuss.elastic.co/t/cluster-locks-up-if-master-node-filesystem-becomes-read-only/38245/3 "2016-01-02T00:51:04Z")

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There are two solutions.

First one is ES-only. The reason why ES is not shutting down automatically is because `org.elasticsearch.env.NodeEnviroment` keeps a `java.nio.file.FileStore` which is never monitored by calling `isReadOnly()` method regularly.

The `java.nio.file.FileStore` of all writable paths would have to be monitored for emergency stop in such kind of event.

To make the cluster drop a node with readonly file store, you would have modify the code and submit a patch.

The second solution: to detect general hardware malfunctions, JVM-based methods are quite not sufficient. Hence, ES is the not the best place to implement that, but the OS. You have to set up server monitoring software which can understand SNMP or IPMI or triggers for mcelog [https://github.com/andikleen/mcelog](https://github.com/andikleen/mcelog) that can kill ES (and other) processes in case of severe events.

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