> For the complete documentation index, see [llms.txt](https://karansingh.gitbook.io/aws-saa-c02/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://karansingh.gitbook.io/aws-saa-c02/elb/stickiness.md).

# Stickiness

* It **enables the load balancer to bind a user's session to a specific instance**.
  * Ensures that **all requests from the user during the session are sent to the same instance**.<br>
* Session stickiness is **defined at a target group level**.<br>
* Elastic Load Balancing **creates a cookie, called AWSELB**, that is **used to map the session to the instance and a duration can be set to that cookie**.<br>
* It **can cause uneven load on backend instances** because some instances might get used more than others.