How to fix SnapshotRestoreException: cannot restore index [index] because it's open in Elasticsearch

# Check status of all indices
curl -X GET "localhost:9200/_cat/indices?v&health=green,yellow,red" -u "username:password"

# Check specific index status
curl -X GET "localhost:9200/my_index" -u "username:password"

# Use the _cat/indices API to see open/closed status
curl -X GET "localhost:9200/_cat/indices/my_index?format=json&h=index,status" -u "username:password"

# Check which indices are included in your snapshot
curl -X GET "localhost:9200/_snapshot/my_repository/my_snapshot" -u "username:password"

# Close the specific index
curl -X POST "localhost:9200/my_index/_close" -u "username:password"

# Verify the index is closed
curl -X GET "localhost:9200/my_index" -u "username:password"
# Should return: {"my_index":{"settings":{"index":{"verified_before_close":"false","creation_date":"...","number_of_shards":"...","number_of_replicas":"...","uuid":"...","version":{"created":"..."},"provided_name":"my_index"}}}}

# For multiple indices, close them all
curl -X POST "localhost:9200/index1,index2,index3/_close" -u "username:password"

# Using wildcards (be careful!)
curl -X POST "localhost:9200/logs-*/_close" -u "username:password"

# Basic restore to original index names
curl -X POST "localhost:9200/_snapshot/my_repository/my_snapshot/_restore?wait_for_completion=true" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "indices": "my_index",
  "ignore_unavailable": false,
  "include_global_state": false
}
'

# Restore with rename pattern (safer for production)
curl -X POST "localhost:9200/_snapshot/my_repository/my_snapshot/_restore?wait_for_completion=true" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "indices": "my_index",
  "ignore_unavailable": false,
  "include_global_state": false,
  "rename_pattern": "(.+)",
  "rename_replacement": "restored_$1"
}
'

# Monitor restore progress
curl -X GET "localhost:9200/_snapshot/my_repository/my_snapshot/_status" -u "username:password"

# Reopen the restored index
curl -X POST "localhost:9200/my_index/_open" -u "username:password"

# Verify the index is open and healthy
curl -X GET "localhost:9200/_cat/indices/my_index?v&health=green" -u "username:password"

# Check index health and document count
curl -X GET "localhost:9200/my_index/_count" -u "username:password"
curl -X GET "localhost:9200/my_index/_search?size=0" -u "username:password"

# If using renamed indices, consider reindexing or alias switching
curl -X POST "localhost:9200/_reindex?wait_for_completion=true" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "source": {
    "index": "restored_my_index"
  },
  "dest": {
    "index": "my_index"
  }
}
'

# 1. Always check index status before restore
curl -X GET "localhost:9200/_cat/indices/my_index?format=json&h=index,status" -u "username:password"

# 2. Create restore scripts with pre-flight checks
#!/bin/bash
INDEX="my_index"
STATUS=$(curl -s -X GET "localhost:9200/_cat/indices/$INDEX?format=json&h=status" -u "username:password" | jq -r '.[0].status')

if [ "$STATUS" = "open" ]; then
  echo "Index $INDEX is open. Closing before restore..."
  curl -X POST "localhost:9200/$INDEX/_close" -u "username:password"
fi

# 3. Use index aliases for zero-downtime restores
curl -X POST "localhost:9200/_aliases" -u "username:password" -H 'Content-Type: application/json' -d'
{
  "actions": [
    {
      "add": {
        "index": "restored_my_index",
        "alias": "my_index"
      }
    },
    {
      "remove": {
        "index": "old_my_index",
        "alias": "my_index"
      }
    }
  ]
}
'

# 4. Schedule restores during maintenance windows
# Use cron or scheduler tools for off-hours operations