In this post I am trying to describe how anyone can increase or decrease the admin user session lifetime, In Magento2 the admin user session lifetime is by default 900 seconds around 15 minutes, so if you want to increase this time, its very easy and can be managed
In Magento 2 it has many security features, Because of security purpose Magento by default disable the admin login share session feature means by default it is not allowing the multiple user login to the admin panel with the same user and password details, it improves security to the