Time Machine completed a verification of your backups. To improve reliability, Time Machine must create a new backup for you.

Not that is current, read the excerpt I posted from Pondini, it is old but seems to disagree with the statement that it does support them. Specifically it states that some NAS may be supported but there are some caveats. Maybe you can provide relevant and current Apple docs?

Pondini documentation is old now.

I do think the issue of TM backup reliability on third party network devices was poorer in the past.

It still is poor with the cheap end stuff.

But Apple changed dramatically at Mavericks .. when they changed from AFP to SMB as the default network protocol.

Since then and with other more diabolical changes to DNS, TM has become far from reliable on a TC or any other network device.

I did use a Zyxel (cheap end) NAS alongside a TC and it did corrupt the TM backup on a couple of occasions.. I made allowance for it and was still happy overall with its performance.

Since moving to the synology it has so far (20months) given no trouble at all. I won't ever say never.. but my last new TC died in less time than that.. !!

Is SMB now the default protocol.

I use a directly connected RAID5 box and have never had any issues (since 1996) but as I don't rely solely on TM it wouldn't matter much if there were,

You are avoiding the question. What Apple support document do you have that says that Time Machine backups are not supported with a NAS?

Please don't try to change the subject with Pondini. Did you even read the part of the Pondini information where he said that.....Time Machine can back up to some NAS drives, but only those that meet the criteria specified in this Apple article:

The "criteria" is in the Apple support documents about Time Machine.

Please also keep in mind that Pondini passed away 3+ years ago.

Unless you can provide an Apple support document to support your statement, we'll consider this closed.

I already answered that, no I did not read any Apple support docs, so consider it as you please.

But the one I did read earlier tonight does not mention NAS at all, so if there is one that does could you point me to it.

Please look back a page or two in the discussion. It's there, but you missed it, obviously.

Have a good evening.

And I am confused by LaPasteneques statement that Apple changed the default protocol from AFP to SMB which contradicts both Bob Timmons and Pondini's assertion that it should use AFP.

It's still so unclear as to what works that I will continue to advise people not to use a NAS. And continue not using one myself.

Then maybe I can avoid corrupt backups that as Bob says, "We do not know why this error sometimes occurs"

An unexplainable error is the worst error a backup can have.

Yikes just got this error for the first time. I'm running a 3TB Airport Time Capsule on my late-2013 iMac running Mavericks.

What concerns me- other than deleting all my backup history- is that most of these reports are on 3rd party NAS devices. Are many Time Capsule users seeing this?

I have an Apple Time Capsule - no 3rd party stuff. Apple built, Apple tested, Apple vetted, Apple blessed. So, no pointing fingers at non Apple stuff.

were you doing the backup over wifi or hard wired ? I had same problem over wifi with 4TB WD MyCloude

Hanani wrote:

were you doing the backup over wifi or hard wired ? I had same problem over wifi with 4TB WD MyCloude

My iMac is connected to my Time Capsule with Ethernet. Got this error for the first time yesterday. Rebuilding backup as we speak.

I Wish you luck! I deserted the over network backuo!

doing backup to. WD passport connected with USB to the Macbook As well as using 3rd party cloud base back up service

A different data point. I've seen this twice now on my home Mac Pro (running 10.6 because of the need for PPC emulation). This is using an Apple Time Capsule, a fairly old one, hardwired. There is no indication that this is a hardware or disk drive issue. As far as I can tell it's a software bug. It is unfortunate that Apple doesn't seem interested in fixing it.

The previous time it happened I did a backup to a spare hard drive just in case TC decided to throw up and have no backups at all. I'll do that again this time (it just happened this morning), I think.

Following up: some more searching turned up this article: http://www.garth.org/archives/2011,08,27,169,fix-time-machine-sparsebundle-nas-b ased-backup-errors.html . I tried it last night, it worked fine. (Very small tweaks were needed: fsck need a /dev/rdiskxxxx, not /dev/diskxxxx.)

So my backups are running again and I didn't lose the old ones.

Paul, have you used this with a Time Capsule? When I try running those commands I get a "No such file or directory" error. Not sure what I'm doing wrong. Any suggestions, please? Thanks.