How to assign static IP

I configured my Rancher instance on a VM in FreeNAS 11.1. At the time it was assigned an IP address of by my DHCP. I created a host, and got a CrashPlan container up and running. Then my physical box rebooted due to a power failure, and now when I boot up, the Rancher instance has an IP address of The host shows as Disconnected, and I cannot access my CrashPlan container. I’m thinking that if I re-assign this instance to ip address .13, the host may connect again and all will be well. (And once that is done, I will configure my DHCP server to reserve that IP Address for this machine).
But how do I do this? How do I configure my Rancher server to this new static IP Address?

Well something interesting has happened. In my FreeNAS GUI, I went to the VM’s tab, and stopped and restarted the VM on which Rancher is running.
It was again assigned IP address .12 by the DHCP, but this time, when I logged back into my rancher UI on port 8080, the Host showed as Connected, and I was able to manage my crashplan container again.
So I immediately configured my DHCP server to reserve address .12 for this VM’s MAC address. But I’d still like to know how to configure the rancher server to use a static IP instead of requesting one from the DHCP server (even though the mentioned address reservation should solve my problem going forward).

The server is a container, it has no control over the IPs on the machine you run it on.

If you are running RancherOS on that VM,

Fantastic. Thanks. I’m still busy getting to grips with rancheros vs rancher server.