Q: Best software to diagnose and repair a mac pro hard drive?

Today's drives take many hours just to read every block. The best way to proceed is to replace the failing drive with a new drive and a fresh Install of Mac OS X, and then use the full power of Mac OS X to debug and salvage the old drive at your leisure.

Some Users have had good luck with Utilities like Disk Warrior, which attempts to salvage the Directory information and construct a new, replacemement Directory and repair-in-place. If the drive is too damaged, it may not work.

A drive with serious damage that Disk Utility cannot repair may be better salvaged with a third-party utility such as Data Rescue. This Utility does not attempt to repair, only finds and copies off to another drive the files it can salvage.

So you need two spare drives to proceed. Luckily, they are cheap.

Shows corrupt... using what and done from where?

What you want(ed) was a 2nd working backup that is bootable; a small 'emergency maintenance system' somewhere (only needs 20GB in size) in addition to Lion Recover Mode.

Carbon Copy Cloner for making bootable backups is excellent. One reason: enable checksum to insure the integrity of every file copied. Ability to easily and selectively copy or ignore folders. Use to backup to another hard drive partitions all your important drive volumes. In addition to TimeMachine.

Data Rescue 3 would be the next step and choice. Demo is free.

A couple new drives. One for system. One for recovery. Maybe a 3rd for redundant backup sets depending on how many backups you have and use now.

Recovery Mode only helps if it is just the directory or you are okay with erasing the system volume.

All your data should not be on the system boot drive.

If you have TimeMachine you can just restore everything to another hard drive.

If you are not using a SSD for your system, then now is the time to do so.

Depending on your needs, work and apps a small $89 128GB is fine, or maybe you need to go all out on a $320 500GB. Or perhaps even knowing how fast an SSD will aide your now 6 yr old Mac, you want a good solid tradition 1TB drive like $108 Seagate Constellation instead.

New system drive. New data drive perhaps. Recovery and backup drive(s).

Magic bullet? only to copy and backup what is not backed up. You dont' say. If you have not been backing up, then maybe just and only maybe, you need to fork over for Data Rescue 3 and/or Alsoft Disk Warrior.

"fixing' or repairing a corrupt disk drive, should only be so you can recover and backup. You (or rather I) would then ERASE the entire drive and restore it after doing a zero-all (3 hrs perhaps?) or use it as an extra backup and not trust the drive again (it is 1 yr old? 5 yrs old?).

I would not continue to use the drive, even if it passed Disk Utility.

What was the exact message from DU by the way?

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ps: Grant said it well in fewer words and didn't see it until after.

With SSD, unless Apple's, I would grab a TRIM enabler program to do so.

Also keep an image of the SSD handy for use.

From time to time boot from another drive iwth TRIM also enabled and run DU's Repair Disk.

your SSD may need to be restored/erased. It should have above average free space too.

An image or partition of a system SSD would be rather small and fit anyway, set aside space for a volume on TimeMachine, an image on data drive etc.

Keep most backups incl. one for system off line so nothing can happen to it, even if you are on UPS and has good 10+ minutes runtime before a needed shutdown.

And DO use a Safe Boot or Recovery Mode ANY time there is a hard freeze or restart. The directory likely needs to be rebuilt and system and user caches often take the brunt of the damage. Just an extra step to do a slower safe boot for insurance rather than assume the system will recognize a dirty condition and use the journal.

Thanks.

Somewhat dated thread, but regarding HDs, specifically with reference to Mac Pro desktops, HDDs are still the most reliable. Almost every SSD we've installed in client desktops have failed at least two times, on the average, in less than two years on each Mac (to one degree or another, some showing signs of impending failure, others simply failed).

That's a FAR greater failure rate than we ever experienced with HDDs (WD Caviar Black) over a 5 year period, supporting a greater number of desktops (Mac Pros). E.g. failures over that 5 year period were two WD HDDs (due to extreme video rendering in a less than ideal environment -- heat, dust, etc).

SSD (flash storage) are, simply put, just too fragile for a business or businesslike environment with heavy processing. We're switching our clients back to HDDs for the OS, critical applications, SSDs for ancillary storage. Our suggestion to others is to do the same. The "slight" benefit of speed from the SSDs vs. HDDs isn't that discernable over the long term and not worth the trade-off for potential, vital data loss.

Are you using TRIM on these drives. Every SSD needs TRIM.

You could install SSD as the Boot/Applications drive, and store user data on a Rotating drive, similar to the dark cylinder Mac Pro organization. That would give you most of the speed of the SSD, but keep User data on more predictable rotating magnetic drives.

User Tip: Creating a lean, fast Boot Drive

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Disabled TRIM quite a while ago for reasons too detailed and time-consuming to go into on a public forum. Briefly, unnecessary despite common opinions that TRIM increases speed of drives, however, speed hasn't been the issue, reliability has been.

Beyond decades of first working in the "Death Star" environment (MS-DOS/PC-DOS, Trash-80s, etc), abandoning Darth Vader (B Gates) almost entirely to support Apple environments (we focus mostly on network support), from client experiences, including an international builder/developer whose IT director insists on HDDs for crucial reliability in data centers, SSDs still cannot match the reliability of a platter drive in a non-hostile environment (even a couple of major So Cal universities in So Cal reverted back to HDDs). Conversely, we still believe they're great for notebooks for obvious reasons.

Grant Bennet-Alder wrote:

 

Are you using TRIM on these drives. Every SSD needs TRIM.

 

You could install SSD as the Boot/Applications drive, and store user data on a Rotating drive, similar to the dark cylinder Mac Pro organization.

With regards to the above thoughts, actually it should be the other way around in a "mission critical" (business office) environment, as we stated "...switching ... to HDDs for the OS, critical applications, SSDs for ancillary storage," since the OS ("boot drive") is the most vital for business environs (even a busy home office). It can be much more time consuming to recover from a backup than it can be to simply access another data storage drive, considering Microsoft applications, VMs, various drivers (printers, etc), etc on the Mac HDs ("boot drives").

Further, TRIM has very little to do with reliability issues. Lastly, failed SSDs experienced absolutely no speed degradation prior to issues, failures. Samsung (most failures) and SanDisk advised circuitry had failed (trans, caps, etc). Power outages, failures would be a more likely cause, but all desktops are on UPSes, outages occurred on a small number of desktops.

Thanks for your thoughts though.

despite common opinions that TRIM increases speed of drives, however, speed hasn't been the issue, reliability has been.

TRIM does NOT increase the speed of SSD drives, except in one very important and diabolical case (which is the reason TRIM is needed at all).

On a rotating magnetic drive, all blocks are pre-allocated. When blocks are deleted, they are simply added to the free space bitmap. This means that the block data are not actually erased, only "made available for re-use". No notification of data deletion its sent to the drive, since none is needed. Each block can be individually replaced with new data at full speed.

On an SSD, only a SuperBlock (much larger that a standard Disk block) can be written. Blocks are dynamically allocated. The problem is that the file system does not tell the drive when a block is deleted, so an SSD drive continues to carry all deleted blocks as if they were perfectly good.

The reported once-in-a-blue-moon SSD slowness (sometimes followed by failure to respond and apparent drive death) occurs when many blocks are filled, and a SuperBlock can not be quickly made available for a new write. At this point, some SSD drives can do an emergency garbage-collect to assemble a free superblock, and some just fall over, apparently dead.

TRIM is the notification to the SSD Drive that certain data blocks have been deleted, so that those data blocks no longer must be carried as "in use" by the drive. This makes drive garbage-collection easier, and avoids the above-described diabolical condition that can cause an SSD to stop responding.

https://en.wikipedia.org/wiki/Trim_(computing)

In my opinion, every SSD drive requires TRIM This is not related to everyday drive speed, it is to avoid the diabolical race condition the drive can get stuck in, and can make the drive appear dead.

Again, thanks for your views.

Enabling Trim on  a SSD. 

I tried to enable TRIM on a Crucial SSD in a 2011 Mac Pro (3.2Ghz quad).  I used terminal to enter

sudo trimforce enable

I got an error message: 

sudo: unable to stat /etc/sudoers: Permission denied

sudo: no valid sudoers sources found, quitting

How can I work around this?  I was able to enable TRIM on my 2009 Mac Pro and my MacBook Pro ....

Richard

It appears your sudoers file (which maintains a privileged list of who may use the Sudo command) is damaged or has bad permissions. You cannot run any sudo commands unless that is working properly.

https://en.wikipedia.org/wiki/Stat_(system_call)

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