# Suddenly Lost data after this 'index not found exception'
**URL:** https://discuss.elastic.co/t/suddenly-lost-data-after-this-index-not-found-exception/35996
**Category:** Elasticsearch
**Created:** [December 1, 2015, 7:56am UTC](https://discuss.elastic.co/t/suddenly-lost-data-after-this-index-not-found-exception/35996 "2015-12-01T07:56:43Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@moni15moni](https://discuss.elastic.co/u/moni15moni)
#### Post date: [December 1, 2015, 7:56am UTC](https://discuss.elastic.co/t/suddenly-lost-data-after-this-index-not-found-exception/35996/1 "2015-12-01T07:56:43Z")
Hi
Today i have faced strange issue, After i am getting cluster alert for red, I have investigated on the particular Node which one is down.
In this node we have 3 shards ,each contains 400 - 500 GB Data.After I got a following exception ,i checked there is data loss and lost every files.
Caused by: org.elasticsearch.index.gateway.IndexShardGatewayRecoveryException: [xindex][0] shard allocated for local recovery (post api), should exist, but doesn't, current files: []
Caused by: org.apache.lucene.index.IndexNotFoundException: no segments\* file found in store(least\_used[rate\_limited(mmapfs(/disk01/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk02/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk03/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk04/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk05/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk06/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk07/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk08/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk09/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0), rate\_limited(mmapfs(/disk10/ESData/elasticsearch/nodes/0/indices/xindex/0/index), type=MERGE, rate=20.0)]): files: []
Can you please explain what is the cause for this exception and how can we override this issues.
Thanks
Moni
---
### Author:  [@system](https://discuss.elastic.co/u/system)
#### Post date: [July 5, 2017, 11:34pm UTC](https://discuss.elastic.co/t/suddenly-lost-data-after-this-index-not-found-exception/35996/2 "2017-07-05T23:34:35Z")