Time Machine not waking Macbook to perform backups

Question

Time Machine not waking Macbook to perform backups

I am backing up a Macbook Pro to a Mac Mini with OS X Server installed. Previously I backed it up to a locally-attached USB hard drive. It's about 1 year old and with Yosemite, it performed hourly backups while sleeping as expected.

In both cases, Time Machine works fine, aside from one thing... The hourly backups do not happen, when the computer is asleep. In other words, the Mac does not wake itself to perform the backup as expected (Power Nap is enabled.)

I have seen other questions similar to this, involving a USB-connected UPS, but I do not have one.

What I've tried:

1. I have done a clean install (with format) of El Capitan from the recovery partition, and did not restore from Time Machine (just dragged my music, photos, documents back to their respective homes manually).

2. I have also reset the SMC and PRAM, with no effect on this issue.

3. I have updated to 10.11.2 and still experience the problem.

4. Switched from locally-attached (USB) target to a network target (on OS X Server) with no change

Starting a backup manually works perfectly, and automatic backups occur as expected while I am using the computer (i.e. as long as it does not go to sleep).

Energy Saver preferences are using defaults, Power Nap is enabled.

So my question is simply... Before I contact support, does anyone know if there is an open bug report for this? I *have* read the other threads and they are very specifically talking about a connected UPS issue and that a fix was imminent in 10.11.2. Any other Macbook owners having this issue?

MacBook Pro (Retina, 15-inch, Mid 2014), OS X El Capitan (10.11.2)

Posted on Dec 22, 2015 4:39 AM

Reply

Answer 1

Dec 22, 2015 4:47 AM in response to DaveDaveyDavid

Time Machine will only wake the Mac to perform a backup, if the Mac is plugged in to an AC power outlet. If you've done that, then it might be a bug for which I don't know a solution.

Reply

Answer 2

Barney-15E

Level 10

123,104 points

Dec 22, 2015 6:14 AM in response to DaveDaveyDavid

Is it successfully completing one backup?

This statement implies it will try until it completes a backup, then stop trying.

Time Machine backups are attempted hourly until a successful backup has been completed.

How Power Nap works on your Mac - Apple Support

I'm not sure what backups are needed while it sleeps once any pre-sleep changes have been backed up.

Reply

Answer 3

Dec 22, 2015 6:17 AM in response to Barney-15E

Very interesting article, Barney-15E.

Yes the computer is plugged into AC power and it has successfully performed an initial backup. Perhaps this is "by design" as I have always wondered what was the point of backing up the computer while it is sleeping, since nothing should be changing. Typically when I wake the computer, it performs a backup almost immediately which is only a few MB.

But the prior behavior, when I would go into Time Machine, I would always see an hourly backup for every hour (sleeping or not) so now the change in behavior made me think it was a bug.

Reply

Answer 4

Barney-15E

Level 10

123,104 points

Dec 22, 2015 7:13 AM in response to DaveDaveyDavid

Looking at my log from last night, it woke about an hour after sleep, ran a backup, then no backups until waking this morning. Other PowerNap tasks took place hourly, but no backups as implied by that statement.

I really don't know how it worked before.

Reply