How to list all the indices in Elasticsearch ?

For listing all the indices from unix command line, type the following command.

curl -X GET http://eshost:9200/_cat/indices

For checking this from the browser, simply type the following URL in the browser

http://eshost:9200/_cat/indices

Where eshost is the hostname of the elasticsearch server. You can replace it with the IP address of the server also. 9200 is the default port used by elasticsearch

Creating Random File of any size in linux

Sometimes we require some random file of some specific size for testing some performance such as file transfer. There are several ways to create such files.

Method 1
If you just want a file with some specific size, you can use the following command.

dd if=/dev/urandom of=dummyfile.txt bs=2G count=1

The bs is the block size, 2G means 2 GB. If you make the count as 2, then 2 GB *2 = 4 GB random file will be generated.

Method 2
If you are concerned about the schema, you can generate the data using a simple approach.
First create a file with a sample data set of 1 or 2 records in a file. Let us call that file name as A.txt

Then using a simple shell script, we can make it very big.



Depending upon the size requirement, you can increase the value of limit to any number.

Method 3
Use any online / offline data generation tools. This will be required only if you need random data with some specific schema and discrete values.
Some useful links are listed below

1) http://www.generatedata.com/
2) http://c2.com/cgi/wiki?TestDataGenerator