Setting up index aliases

Index aliases let you create aliases for one or more indexes or index name patterns. We will cover the following topics in order to learn how index aliases work:

• Understanding index aliases
• How index aliases can help

Understanding index aliases

An index alias just provides an extra name to refer to an index; it can be defined in the following way:

POST /_aliases
{
  "actions" : [
    { "add" : { "index" : "index1", "alias" : "current_index" } }
  ]
}

Here, index1 can be referred to with the alias current_index. Similarly, the index alias can be removed with the remove action of the _aliases REST API:

POST /_aliases
{
  "actions" : [
    { "remove" : { "index" : "index1", "alias" : "current_index" } }
  ]
}

The preceding call will remove the alias current_index. Two actions can be combined in a single invocation of the _aliases API. When two calls are combined, the operations are done automatically. For example, the following call would be completely transparent to the client...