It is true that the so-called software readiness of one of the three computers on the ISS was lost, in other words there was a software failure. In order to restore the computer to good working order, the computer needs to be restarted. This reported by Roscosmos.

This failure is not going to affect the ISS operations in any way. The nominal timeline allows for an indefinite operation on as few as two computers. But in order to be confident in the reliability of the docking with Progress in November, we are going to reboot on November 8, 2018.

There is no need to replace the computer.