Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss

Time Machine question

0 views
Skip to first unread message

Michael Fogler

unread,
Jan 4, 2010, 8:18:00 AM1/4/10
to
I asked this before, but now I have more information.

iMac 2.66 GHz, 4GB Ram. I have a Western Digital 500GB external drive
used by Time Machine. Recently, all of the sudden I will get the
message that Time Machine can't backup because the disk appears to be
read only. I can launch Disk Utility, run Verify Disk (repair disk
isn't available at that point) and it finds nothing wrong. After
that, the disk now has that I can read and write. When I get the
message that the backup disk appears to be read only, I can also eject
the disk, unplug it and plug it back in, and then the disk shows that I
can read and write. There are 2 users on this machine, one admin, one
standard, but it doesn't seem to matter whether one or both users are
logged in when this happens.

Does anyone have any ideas on this?

thanks,
--
Michael Fogler
http://michaelfogler.com

Paul Sture

unread,
Jan 4, 2010, 7:09:47 PM1/4/10
to
In article <hhspq8$ffl$1...@solani.org>,
Michael Fogler <guit...@michaelfogler.com> wrote:

I had a different symptom recently, where after a power cut Time Machine
claimed that my external WD drive had "Ignore ownership on this volume"
set. It didn't, even after dismounting and remounting.

A reboot solved it in my case.

Are you using the "Turbo driver" that came with the WD drive? I didn't
install that on my system, since I found a cryptic comment on their web
site which said that later versions of OS X give that speed up anyway.

--
Paul Sture

Michael Fogler

unread,
Jan 5, 2010, 7:59:02 AM1/5/10
to

I don't even know about Turbo driver, so I guess I'm not using it. I
think I've narrowed this down that mine shows up as read only after the
boot up in the morning (I shut down the computer each night before
going to bed). This morning when I saw that the drive was said to be
read only, I logged out and logged back in. And that returned the
drive to read and write. Pretty strange. Any ideas?

Kevin McMurtrie

unread,
Jan 6, 2010, 12:08:47 PM1/6/10
to
In article <hhspq8$ffl$1...@solani.org>,
Michael Fogler <guit...@michaelfogler.com> wrote:

Mac OS X runs older unix permissions and newer hierarchical access
control lists (ACLs) simultaneously in HFS+ disks. Unfortunately,
support for it is extremely broken.

Sometimes you can eliminate broken ACLs with this run as 'root' on the
command line:

chflags -R nouchg noschg /Volumes/your_disk_name

chmod -N -R /Volumes/your_disk_name

Do this for your backup disk only.
--
I won't see Google Groups replies because I must filter them as spam

Michael Fogler

unread,
Jan 6, 2010, 12:25:21 PM1/6/10
to
Is this done in Terminal? If so, how would I do this for backup disk only?

Paul Sture

unread,
Jan 7, 2010, 7:19:49 AM1/7/10
to
In article <hi2h21$39j$1...@solani.org>,
Michael Fogler <guit...@michaelfogler.com> wrote:

Yes, it is done in Terminal. To run as root, do the following in
Terminal:

sudo sh

and give it your admin password when requested.

You can see "your_disk_name" in Finder. For example, I've named my Time
Machine disk "TM", so the commands on my system would be

chflags -R nouchg noschg /Volumes/TM
chmod -N -R /Volumes/TM

--
Paul Sture

Paul Sture

unread,
Jan 7, 2010, 7:21:14 AM1/7/10
to
In article <hhvd2m$r36$3...@solani.org>,
Michael Fogler <guit...@michaelfogler.com> wrote:

Are your disk cables seated correctly (power cables too)?

--
Paul Sture

Michael Fogler

unread,
Jan 7, 2010, 7:57:51 AM1/7/10
to
On 2010-01-07 07:21:14 -0500, Paul Sture said:
>>
>> I don't even know about Turbo driver, so I guess I'm not using it. I
>> think I've narrowed this down that mine shows up as read only after the
>> boot up in the morning (I shut down the computer each night before
>> going to bed). This morning when I saw that the drive was said to be
>> read only, I logged out and logged back in. And that returned the
>> drive to read and write. Pretty strange. Any ideas?
>
> Are your disk cables seated correctly (power cables too)?
I guess so. Not sure what you mean by this. But they seem to be
plugged in firmly.

Paul Sture

unread,
Jan 7, 2010, 9:02:23 AM1/7/10
to
In article <hi4lof$jej$3...@solani.org>,
Michael Fogler <guit...@michaelfogler.com> wrote:

It's just that I've had problems in the past with cables not being
plugged in fully. This was probably more common in the days when
connectors were larger.

What happens if you manually wake the drive up by pressing the switch on
the drive before you log on?

I forgot to ask. Are you using USB or Firewire for this drive?

--
Paul Sture

Michael Fogler

unread,
Jan 7, 2010, 5:56:58 PM1/7/10
to
On 2010-01-07 09:02:23 -0500, Paul Sture said:

> It's just that I've had problems in the past with cables not being
> plugged in fully. This was probably more common in the days when
> connectors were larger.
>
> What happens if you manually wake the drive up by pressing the switch on
> the drive before you log on?

I don't think there is an on switch on the drive itself.

>
> I forgot to ask. Are you using USB or Firewire for this drive?

USB (that's all that's offered on this drive.

0 new messages