Disaster recovery backup

Please, any help how to backup RouterOS for disaster recovery.
(not only configuration, OS also)

Thank You

There is no official method for this. You can create two identical routers and use VRRP for this.
http://www.mikrotik.com/testdocs/ros/3.0/ha/vrrp.php

Thank you Normis

What about if ROuterOS crashes. What we can do for lousing not the license? Any backup restore of OS, how to?

if RouterOS would crash, the license will not be destroyed.

Even if new installation of OS is needed (installed on PC)?

new installation requires the purchase of a new key, if you use the same HDD, no new key is needed, even in another PC

OK. Thank you again Normis.

I have an open thread, what about it please. http://forum.mikrotik.com/t/load-balancing-over-multiple-gateways-and-proxy/27485/1