We currently have our ntp set to a fqdn which then round robins the domain controller for time sync. When the Netapp is set to use the fqdn time sync fails, however point it directly at a dedicated NTP source and it syncs fine.
Is there an issue using a Windows DC for time sync with a NetApp? Or does the DC need to be configured to response to non windows time requests?
#NTP and Windows DCs
oak palm
surreal stone
Windows uses SNTP which is slightly different than NTP. There are Other vendors that rely on ntp and also have issues with Microsoft as time servers.
I tell customers worst case, set a pair of switches to ntp master stratum 2 or 3. Then point everything at them (that is if you cannot afford a real time server)
Point the windows dcs to the switches to get time. They become the next stratum level and work fine for windows clients. Continue to point everything else at the switches
shrewd lantern
...or just open your firewall to let everything to pool.ntp.org through 🙂
but yeah, you can use a Windows DC as NTP server but you have to edit the registry so that it speaks "full" NTP. I forgot what needs to be changed but I remember it was not that big of a deal
surreal stone
until a windows update "fixes" the registry back
gusty river
windows servers drift terribly within what a normal ntp server normally would do as well
one place where i worked simply had old laptops with freebsd and ntpd installed throughout the world as stratum 1 boxes, although it shouldn't be too hard to make something that had a gps antenna. hardware clocks with gps/gnss syncing aren't too terribly expensive anyway.
shrewd lantern
this is not limited to Windows. Linux drifts the same if you rely on its internal clock. That's why you sync to an external NTP server, either over the internet or to a GPS receiver. On Windows AND on Linux. Everything else will just fail at some point. I don't see any need of a GPS-based receiver (especially since these need an antenna to get a good signal which can be tricky in a datacenter) and would instead just open a firewall port to a public NTP server which is good enough for 99.9% of all use-cases
surreal stone
Unless you have air gapped/secure networks where that’s actually impossible
gusty river
this is not limited to Windows. Linux drifts the same if you rely on its interna...
linux or a unix system with ntpd or "chrony" installed is going to track internal drift against external time sources (when configured as such) and use that drift to self-correct pretty well where windows just drifts many ms while polling an ntp server without actually giving a crap