A bit of help/explanation required. My PI server and PI interfaces are on different networks separated by a firewall. I can't use a NTP server to synchronise the time of the interfaces and PI server automatically to GMT for various IT issues, so I was wondering what the best way is of keeping them "synchronised" manually. Previously people have been just adjusting the clocks on the interfaces to match the PI server, but sometimes the PI server time drifts from GMT, so that has been manually adjusted as well using its clock, and I've ended up with some PI tags no longer updating (maybe it was coincidence, but its happened more than once when the same sequence of events has occurred). I don't want to keep on rebooting PI interfaces or the PI server whenever I adjust the clocks, so I was wondering what is the best sequence of steps to manually adjust the clocks for those machines which drift. I know the PI interfaces have a time offset to the PI server which it picks up, but I can't remember how that affects the timestamp of the data between the PI server and PI interface.
Any help/explanations appreciated!