Did the console port can connect to RJ11 port?

There is a RJ11 port on my server, I need connnect to RJ11 port from the RJ45 port of CM 16. Could I do this? And what’s the pin define of RJ11?

This should be possible. There is no standard for RJ11, you will need to obtain the RJ11 pin-outs from your server vendor in order to accommodate the wiring.