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- Nlnmad.thehocklocker.com › Mac-cannot-ejectMac Cannot Eject External Hard Drive
- Eject Hard Drive Safely
- How To Eject On A Mac
- There is the concept of an in-use bit. If you have a file opened from that external drive, or you have actually told Finder to navigate to a folder location on it, the operating system will not eject it because it is 'in-use.' For instance, I have a folder mounted from my DiskStation NAS, and I clicked a folder on it from the Finder.
- If you try to eject an external hard drive on the mac but it says it is in use then you need to give this fix a try. Not Able To Eject External Hard Disk Mac; External Hard Drive Mac Pc; Summary: 5 ways to eject an external drive from a Mac. Pick your favorite way to eject disk volumes from your Mac and put an end to the Disk Not Ejected.
Is it necessary or recommended practice to eject external drives before logging out, restarting, or shutting down? (The drives are not being unplugged.)
BTW, I am aware that I need to eject my external drives before unplugging them, I just don't know if it's necessary when logging out or shutting down. It seems to me this should be obvious, but I can't find an explicit answer to this question anywhere. I am interested in answers for Snow Leopard, Lion & Mountain Lion OS versions, as I have 2 machines, one with Snow Leopard, the other with Lion, & I'll soon be upgrading Lion to Mountain Lion.
Phil MPhil M“Macintosh HD” is an internal MacBook drive, and “Elements” is my external hard drive. So, in my case, the name of the disk is “Elements”. In your case, the disc name will be different. The below commands assume this is Elements, but replace Elements with the correct disk name if it’s something different. Sleep Eject is a small App available for $0.99 in the Mac App Store that ejects all mounted drives when your system goes to sleep. This means if you do need to remove a drive from your system, you need not waste time waking it up first. Sleep Eject can be used to eject all mounted drives, or just left running so that when your system sleeps, it.
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1No, it's only recommended when unplugging the cable.
The reason why you eject is so that any processes reading and writing from the disk will cause OS X to notify you of the disk being in use and prevent data corruption that can occur by just unplugging the disk while it's in use.
Additionally the OS might queue different write operations to a cache before actually writing them to disk, and ejecting will make sure these are flushed to the drive before it is disconnected.
Halting any processes from reading/writing to the disk and flushing the caches is implied when rebooting or shutting down the machine (unless you do a cold shutdown by pressing and holding the power button to turn it off). When logging out, the OS can flush the cache at its own discretion.
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GerryGerryNlnmad.thehocklocker.com › Mac-cannot-ejectMac Cannot Eject External Hard Drive
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1There is nothing to gain from explicitly 'ejecting' drives before logging pout, shutting down, or restarting in a normal fashion. MacOS X has a subsystem called 'Disk Arbitration' (primarily the system daemon process 'diskarbitrationd') which mounts drives other than the boot device when a user logs in and unmounts (a.k.a. 'ejects') them when the user logs out. Because it operates outside of the context of a user login session, diskarbitrationd is able to assure that processes which are not directly managed by a user (Spotlight indexing, Time Machine, other users' login sessions, etc.) are dealt with correctly when unmounting devices. It also checks for (& usually can quietly repair) filesystem corruption issues before mounting drives. At a deeper level, the OS also has a daemon (update) which flushes the filesystem cache to disk every 30 seconds and a carefully scripted process for shutting down (i.e. the first half of restarting) which assures that all filesystem devices are properly synched and unmounted before resetting or powering down the system. MacOS X is unique in this respect only in the fine details: all significant OS's have matured beyond the need to have users manually assure that drives aren't unmounted in a 'dirty' state.
The possible exceptions would be if you do something outside of the operating system to halt or reset the system, such as disconnecting the main power or forcing a hardware reset by a long-press of the power switch. Both could cause filesystem corruption, but no one should be taking such steps except in rare and severe cases where one likely won't have the luxury of being able to manually eject drives. (e.g. smoke, flames, kernel panics, etc.)
Bill ColeBill Cole
1No. The short answer is that you eject/unmount a storage device when you no longer wish to use it.
How to find external cd drive on mac. It is perfectly fine to leave an external drive plugged in if you want it available later for yourself or others (such as a Time Machine back up).
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