David writes: > With chrony, you can monitor the RTC over time and adjust the system > clock in accordance with its drift rate at boot time, without > correcting the RTC itself, or you can actually set the RTC from the > system clock periodically.
That leads to the probelem that started this thread: system time being set incorrectly at boot and then stepped later. > The particular problem at shutdown is that there were/are systems, as > you described, that write the system time to the RTC without > necessarily regarding how you might be running the clock otherwise. > That alteration is unknowable for chrony when it restarts after > booting. Obviously you must make sure that only one process ever writes to the RTC. Actually you need never write to the RTC at all: just track its offset and drift rate. That would require hacking the boot process to make sure only your code ever reads it, though. -- John Hasler j...@sugarbit.com Elmwood, WI USA