At the top of this blog post about custom routing, there is a disclaimer that the information is outdated and no longer recommended. There is no link to what is considered the current information.
Does the disclaimer imply that custom routing shouldn't be used at all any more? If so, how are we supposed to solve the "hotspot" problem alluded to in the post? And how can one attain the performance benefits referenced in the "Custom Routing is FAST" section?
That blog post is from 2013, that is why there is a disclaimer.
You can still do routing.
Right, I get that you can still do it since it's obviously documented and still works. The wording of the disclaimer suggests that there is now a preferred alternative to solving these problems. If that's not the case - and the disclaimer was simply slapped on all blog posts of a certain age - then that's a different matter entirely.
That's it.
But I'll pass on the comments to the website team, maybe we can clear it up some more 
Thank you for the confirmation!
© 2020. All Rights Reserved - Elasticsearch
Apache, Apache Lucene, Apache Hadoop, Hadoop, HDFS and the yellow elephant logo are trademarks of the Apache Software Foundation in the United States and/or other countries.