Telstra had the redundancy. They had multiple timing services, local and international. Their dumb mistake was to make a 22 year old gps based clock system as a tier 1 time server, overriding all the other clocks.
Surely there should be settings in their NTP clients regarding skew as well. If you’re trucking along and then your time server says, “Hey I know we’ve been sync’d within 3 milliseconds for years now, but you just need to step the time back 19.8 years real quick for me”, then that should raise a tiny red flag with your client?
They normally do, NTP will reject timestamps too far out of range by default. You can override it but you’d only ever do that if the device has no local RTC and also no way to persist timestamps between reboots.
Telstra had the redundancy. They had multiple timing services, local and international. Their dumb mistake was to make a 22 year old gps based clock system as a tier 1 time server, overriding all the other clocks.
Surely there should be settings in their NTP clients regarding skew as well. If you’re trucking along and then your time server says, “Hey I know we’ve been sync’d within 3 milliseconds for years now, but you just need to step the time back 19.8 years real quick for me”, then that should raise a tiny red flag with your client?
They normally do, NTP will reject timestamps too far out of range by default. You can override it but you’d only ever do that if the device has no local RTC and also no way to persist timestamps between reboots.