2 USB Drives/Hub/AEBS-One Disconnecting when accessed, one does Not.

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Level 1

40 points

2 USB Drives/Hub/AEBS-One Disconnecting when accessed, one does Not.

Greetings,

i have two identical 2.5 USB drives connected to a powered USB hub, connected to a (single radio) AEBS accessed by a 2011 MBP running Lion.

One drive mounts on desktop reliably (via login items) and can be used normally, the other drive mounts intermittently and when mounted, cannot handle a sustained transfer over a few GB.

The drive dismounts with this message: Volume “MMA+” can not be used and will be ejected because it is no longer available. It than usually cannot be seen again until I reboot the AEBS or the drive.

One drive mounts with it's custom icon, the reluctant drive gets a generic blue (remote volume?) icon almost each time it mounts. Occasionally it mounts showing "0" items until re-connected.

I have turned off "put drives to sleep" in Energy Saver.

Both recently got Diskwarrior etc. treatment and are fine.

Any ideas what this may be, or how to remedy it?

SG

Posted on Jun 17, 2012 9:04 AM

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Answer 1

HACKINT0SH

Level 5

5,804 points

Jun 17, 2012 8:36 PM in response to StudioGeek

cannot handle a sustained transfer over a few GB.

Not to over-look the obvious, but certain formats, i.e. Fat32 can only handle file sizes of a few GB 😝

If this isn't the issue, then we can maybe examine a bit deeper....

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Answer 2

StudioGeek Author

Level 1

40 points

Jun 18, 2012 7:55 PM in response to HACKINT0SH

Greetings,

It is formatted APM, Extended (journalled).

Thank You,

SG

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Answer 3

Jun 18, 2012 8:02 PM in response to StudioGeek

Apple says that FAT 16, FAT32 and Mac OS Extended (Journaled) will work with the AirPort Extreme. That appears to be it, as no other formats are mentioned.

The AirPort Extreme (802.11n) and Time Capsule support USB storage devices that are formatted as Mac OS Extended (HFS-plus), FAT16, or FAT32. Formatting a storage device as Mac OS Extended with journaling is recommended, as it may provide some more resilience if the device is removed or powered down while in use.

http://support.apple.com/kb/HT2426

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Answer 4

StudioGeek Author

Level 1

40 points

Jun 20, 2012 8:24 AM in response to Bob Timmons

It is Mac OS Extended (Journaled).

SG

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Answer 5

Jun 20, 2012 9:53 AM in response to StudioGeek

I only use GUID, not Apple Partition Map, so can't say if this makes a difference or not. If your other drive is APM as well, has all the updates, etc., I am out of ideas. Maybe another user can help.

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