For example, topics like MySQL Database remote connection might be caused by this TCP vs Socket issue.
Adding the socket to the chroot might be a solution, but I have not researched the security implications. See this related post: linux - Webserver: chrooted PHP gives mysql.sock error when attempting to reach mysql - Server Fault
And while on the topic of chroot, maybe also check Unable tos end email with jailkit enabled - #13 by hescominsoon