Change record status: 
Project: 
Introduced in branch: 
11.2.x
Introduced in version: 
11.2.0
Description: 

Examples for adding a route alias and for deprecating a route are as follows.

Alias

example.overview:
  alias: example.index

Deprecation

example.overview:
  deprecated:
    package: 'drupal/example'
    version: '11.2'
    message: 'The example.overview route is deprecated in drupal:11.2.0 and is removed in drupal:12.0.0. Use the "example.overview_new." route instead.'

Symfony 5.4 added support for aliases

Impacts: 
Module developers