An open community 
of Macintosh users,
for Macintosh users.

FineTunedMac Dashboard widget now available! Download Here

Topic Options
#23044 - 08/12/12 10:29 AM TIME MACHINE - Available Discs
MG2009 Offline


Registered: 08/05/09
I have just noticed a little issue that does not seem to be posing any (obvious) problems . . . just one of those annoyances that I cannot seem to rectify.

I use one TIME MACHINE for b/u. When I go into SYSTEM PREFERENCES for Time Machine and choose the tab "Select Disk", the dialogue box shows two categories from which to choose:

1. Backup Disks
2. Other Available Disks

An icon (with DATA) for the external HD (i.e. TM) appears in both places. When I use to mouse to hover over the icon in #2 above, my name appears after the afp://. However, when I hover over the icon in #1 above, the same info appears BUT with other miscellaneous characters inserted (e.g. %, AUTH, SRP).

If I click on the icon in #2, the only option tab 'Use Disk' appears. If I click on the icon in #1, the only option tab to 'Remove Disk' appears.

Anybody have any idea what to make of this? Why would one (the same one) HD appear as both the "back up" disk and an "other available" disk? What would account for the discrepancy in the names of the same source disk (i.e. %, AUTH, SRP)?

P.S. TM has not been partitioned in any way as far as I know (at least, not deliberately by any human hands!)

Thanks for any comfort you can provide. crazy

P.S. MBPro (2011) with OSX 10.8 (Mountain Lion) and TC.

Top
#23049 - 08/12/12 10:56 PM Re: TIME MACHINE - Available Discs [Re: MG2009]
tacit Offline


Registered: 08/03/09
Loc: Portland, Oregon, USA
It seems like you may have file sharing turned on, so Time Machine is seeing the disk twice: once attached to your computer, and once when it searches for file servers (it will find a file server even if that file server just so happens to be on the same computer as Time Machine is on). If you remove it from the local pool and add it from the file server pool, it will do the backup over the network rather than directly...which, yes, means your computer would be talking to itself on the network.

SRP is Secure Remote Password protocol. I believe AUTH is Apple's Time Machine over AFP thing, though I'm not sure about that.
_________________________
Photo gallery, all about me, and more: www.xeromag.com/franklin.html

Top
#23050 - 08/13/12 02:21 AM Re: TIME MACHINE - Available Discs [Re: tacit]
MG2009 Offline


Registered: 08/05/09
Thanks for your response, but I understood nothing after:

" . . . It seems like you may have file sharing turned on . . . "

confused

P.S. And, no, the only "sharing" that is turned on in SYSTEM PREFERENCES is for the printer - nothing else.




Top
#23051 - 08/13/12 05:21 AM Re: TIME MACHINE - Available Discs [Re: MG2009]
joemikeb Offline

Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
My system works exactly the same way yours does, with essentially the same indications. What you are seeing is normal behavior. The option to "Remove disk" that you are seeing when the Backup Disk is selected is perhaps a bit misleadingly labeled, but it means to disconnect from it as the current Time Machine backup drive. When I hover over the "Other disks" all of the other potentially usable volumes show up as AFP (Apple Filing Protocol) addresses which is to be expected. The %, AUTH, SRP suffixes would seem to indicate specific authentication and password protection on the particular volume. Without knowing complete details of your Time Machine drive, its formatting, partitioning scheme (your drive is partitioned even if it only has one partition), attachment to your computer, and other arcane details all I can do is speculate. However, from what I observe around here, what you are seeing is 100% normal behavior.

Your Time Machine drive shows up under Backup Disk and again under the list of "Other Available Disks" because Time Machine backups are contained in a Sparse Image Bundle, which is a special type of Sparse Image File. When a Sparse Image Bundle is opened it "mounts" as if it were a physical partition or volume. It is possible to have multiple Sparse Image Bundles on a single drive (In my case there are three separate sparse image bundles on my Time Capsule drive, one is a backup of my iMac, one is a backup of my wife's MacMini, and the third a backup of our MacBook Air). Selecting the same drive under "Other Available Disk" would have the effect of forcing Time Machine to create a new Time Machine sparse image bundle on the drive and fill it with a new Time Machine backup set from your hard drive.
_________________________
joemikeb • moderator

Top
#23053 - 08/13/12 10:28 AM Re: TIME MACHINE - Available Discs [Re: joemikeb]
MG2009 Offline


Registered: 08/05/09
Thanks very much for your response. I am no tech whiz, but I (believe) I followed your thinking/explanation.

If I do understand correctly - that only the one icon with my name whch appears in the "backup" disk column (i.e. referred to as #1 in my original post) - is currently the only one place where I am backing up my computer's contents.

P.S. With the second icon showing under "other available disks", I was puzzled that I had somehow (inadvertently) created a second backup TM on the TC and was concerned that part of my data was in one place and the rest was in another - albeit, split but on the same TC . . . OR, that I was somehow copying all the contents TWICE - in both spots - causing a complete duplicate set whenever I ran TM. Holy Overkill, Batman!!!


On a related matter: There is an option to ENCRYPT the TC/TM data. Is this recommended? What, if any, would be the "downside" of doing so?



smirk

Top
#23056 - 08/13/12 02:17 PM Re: TIME MACHINE - Available Discs [Re: MG2009]
joemikeb Offline

Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
If you are paranoid about someone obtaining your backed up data then encryption is a viable option. The downside of encrypting the backup would be if you lost or forgot the backup password in which case you would be unable to restore any files from the backup.
_________________________
joemikeb • moderator

Top
#23057 - 08/13/12 08:09 PM Re: TIME MACHINE - Available Discs [Re: joemikeb]
MG2009 Offline


Registered: 08/05/09
Thanks a heap . . . and another clear answer. Much appreciated.

grin

Top
#23059 - 08/13/12 09:43 PM Re: TIME MACHINE - Available Discs [Re: joemikeb]
tacit Offline


Registered: 08/03/09
Loc: Portland, Oregon, USA
Originally Posted By: joemikeb
If you are paranoid about someone obtaining your backed up data then encryption is a viable option. The downside of encrypting the backup would be if you lost or forgot the backup password in which case you would be unable to restore any files from the backup.


I'm not entirely sure that's the case, because I seem to recall that at least some "cloud" backup services have a provision in their Ts & Cs that say that they may have a back door decryption key for encrypted data, presumably for law enforcement purposes.

There have already been precedents that remote storage companies may be served with subpoenas for data that they store for private individuals, and are barred by law from informing the owners of the files about the subpoena. As more and more folks move data into the cloud, I suspect that will become more commonplace. It's an area of law where the balance seems to be tilted in favor of law enforcement over the rights of the people who store files remotely, and I suspect this area of law won't be thoroughly thrashed out for years, or perhaps decades.
_________________________
Photo gallery, all about me, and more: www.xeromag.com/franklin.html

Top
#23065 - 08/14/12 08:31 AM TIME MACHINE - individual backups [Re: tacit]
pbGuy Offline


Registered: 08/04/09
Loc: Portland, Oregon
This is a TM question, although off the topic about available discs.

When I look inside the TM Backups.backupdb folder (and the subsequent folder wherein the actual backups are found), I see the periodic, daily backup folders.

Can one safely, manually delete any of those dated - daily backup folders?

- While I've presently got plenty of backup space on the drive, which TM is using, I'm curious if manual deletion of old backups can be done to free space without causing unintended problems.
_________________________
MBP15 i7 (2017) - 1TB PCIe-SSD - 10.14.4, iPhone X & iPadPro 11 WiFi, Watch4

Top
#23067 - 08/14/12 09:27 AM Re: TIME MACHINE - individual backups [Re: pbGuy]
cyn Online

Administrator

Registered: 08/03/09
Please start a new thread for your question.
_________________________
FineTunedMac Forums Admin

Top
#23071 - 08/14/12 11:23 AM Re: TIME MACHINE - individual backups [Re: cyn]
pbGuy Offline


Registered: 08/04/09
Loc: Portland, Oregon
Originally Posted By: cyn
Please start a new thread for your question.


see new thread

Time Machine dated backup folders
_________________________
MBP15 i7 (2017) - 1TB PCIe-SSD - 10.14.4, iPhone X & iPadPro 11 WiFi, Watch4

Top

Moderator:  alternaut, dkmarsh, joemikeb