Q: How do Power Nap, Standby Mode & AutoPowerOff play together?
Good morning,
Background/System & Configuration: This is related to a small office network for which I have written a custom backup script that I am testing before deploying. The script rsyncs selected files from the workstation (2013 Mac Pro, OS X 10.11.6) to the server via wifi through an Airport Extreme. Password-less SSH is used by root to connect from the workstation to the server. The server is a Late 2014 Mac Mini (OS X 10.11.6/Server 5.1.7) set to not sleep.
The script is loaded from launchd and is set to run at designated times throughout the day and night. It seems to work fine when the workstation is awake. I have read that launchd will run scheduled events when a computer wakes from sleep. What I actually seem to experience at night (when I am personally in sleep mode) is that the script will run intermittently (i.e., not at the scheduled times) but it fails because the initial SSH (from rsync) operation times out. The server's full hostname is used in the script, vice the IP address.
On the workstation, Power Nap is enabled and the computer is allowed to sleep. pmset standbydelay=10800 (3 hrs) and autopoweroffdelay=14400 (4 hrs). My understanding is that information in Mail, Notes, Contacts, etc., will only be updated if those apps are running; on my computer, I believe Notes was the only one running over night.
Assumptions:
1) Power Nap is allowing the script to run because the computer has partial wake-ups during the night.
2) The script is falling at night because the workstation's energy saving modes do not allow DNS queries.
Next Test: I will set standbydelay and autopoweroffdelay each to 12 hours and see if the script runs correctly tonight.
Questions:
1) Do my assumptions seem valid?
2) Which of these energy sleep modes disables DNS lookups or other network activity?
3) Does anyone have a link to good documentation describing the technical interactions between services when Power Nap is active?
Thanks in advance.
Mac Pro, OS X El Capitan (10.11.6), null
Posted on Aug 19, 2016 6:25 AM
Hi Tim,
Disable power management on your Server and Workstations until all scripts, logins etc. are functioning. Then reintroduce gradually the power mgmt. settings, checking functionality at each step.
i.e.: - Disable all sleep & wake schedules and settings, within System Preferences -> Energy Saver and perform SMC resets on the Server and Workstations. Refer: Reset the System Management Controller (SMC) on your Mac - Apple Support
HTH
Cheers, dwbrecovery
Posted on Aug 24, 2016 5:19 PM