Remember when Migration Assistant worked with Disk Images?

Apple Disk Image IconI don’t exactly recall when Apple’s Migration Assistant started logging out the user (10.9ish), but since then it has been a little more irritating to migrate from a dmg or other image format (as opposed to a source hard drive or time machine backup).  Here is a simple Terminal command to mount the image as root and thus keep it mounted after logout.

sudo hdiutil attach diskimage.dmg

This process does require running a checksum, and for larger images that could take a while.  Once you run this command and it completes its verification of the disk image, simply run Migration Assistant and complete the migration.  After migration and a restart, the image is unmounted and you are ready to work on your newly migrated mac. (note: migration can also take quite a while depending on the amount of data)

Throwback Thursday! Remembering Mac Talk!

I needed a part in Woodland hills this week so I decided to drop by my old employer, Mac Talk, Inc.  Unfortunately, it could not be found.  Apparently, it closed up shop unceremoniously and I never knew.  I had a long and sorted history with the company stretching back across several owners (and decades).  Here are a few pictures I found.  What ever happened to Moe and Shilla?  or Steve?MacTalk Storefront Continue reading “Throwback Thursday! Remembering Mac Talk!”

Apple is getting between me and my TRIM!

At the device level, SSD drives function entirely differently then conventional mechanical disks.  As a result, the way that operating systems traditionally use these devices lead to progressive performance degradation and even shortened lifespan.  Technology was needed to offset this failing.  Enter TRIM.  Apple introduced it in 2011, but believe it or not, even today, Apple refuses to automatically enable TRIM for 3rd party SSD drives.  Not only that, but if you manually enable it yourself, it is then disabled during any OS upgrade (i.e. 10.9.1-10.9.3).  You can check your TRIM status from the System Profiler/System Information under SATA by selecting your device.  I switched my favorite utility from Chameleon SSD Optimizer to Trim Enabler.  I made the change for two reasons.  First, Chameleon has some compatibility issues.  Second, Trim Enabler has a feature to check on startup.  Makes it easier to reenable after a software update.

I found a great utility to enable TRIM on 10.6.8-10.9.5: Trim Enabler
Don’t forget to reenable it after each OS X System Update.

Technical Details from Wikipedia:

Because of the way that file systems typically handle delete operations, storage media (SSDs, but also traditional hard drives) generally do not know which sectors/pages are truly in use and which can be considered free space. Delete operations are typically limited to flagging data blocks as “not in use” in the file system.[6][7] Contrary to, for example, an overwrite operation, a delete will therefore not involve a physical write to the sectors that contain the data. Since a common SSD has no knowledge of the file system structures, including the list of unused blocks/sectors, the storage medium remains unaware that the blocks have become available. While this often enables undelete tools to recover files from traditional hard disks,[7][8] despite the files being reported as “deleted” by the operating system, it also means that when the operating system later performs a write operation to one of the sectors, which it considers free space, it effectively becomes an overwrite operation from the point of view of the storage medium. For traditional hard disks, this is no different from writing an empty sector, but because of how some SSDs function at the lowest level, an overwrite produces significant overhead compared to writing data into an empty page, potentially crippling write performance.[7][9]

SSDs store data in flash memory cells that are grouped into pages, with the pages (typically 4 to 16 kB each) grouped together into blocks (typically 128 to 512 pages per block, e.g. totaling 512 kB per block in case of the 4/128 combination).[6][10] NAND flash memory cells can only be directly written to when they are empty. If they are considered to contain data, the contents first need to be erased before a write operation can be performed reliably. In SSDs, a write operation can be done on the page-level, but due to hardware limitations, erase commands always affect entire blocks.[10] As a result, writing data to SSD media is very fast as long as empty pages can be used, but slows down considerably once previously written pages need to be overwritten. Since an erase of the cells in the page is needed before it can be written again, but only entire blocks can be erased, an overwrite will initiate a read-erase-modify-write cycle:[6][11] the contents of the entire block have to be stored in cache before it is effectively erased on the flash medium, then the overwritten page is modified in the cache so the cached block is up to date, and only then is the entire block (with updated page) written to the flash medium. This phenomenon is known as write amplification.[12][13]

Oh no, not again! Apple firewire exploit published!

Firewire Symbol
This is Deja Vu of an attack from years ago where RAM was accessed from the firewire buss.  This study published back in Sept 2011 (that i am late to discover) revisits this attack on Lion.  Security researchers from frameloss published the specifics on an attack and how to avoid it.  Learn how your password could be extracted from your computer’s memory via your firewire port.  Even when you thought it was locked!  Even with FileVault!

Mostly you must turn off fast user switching, and activate a feature that dumps the password for added security.   read all about it here. . .

http://www.frameloss.org/2011/09/18/firewire-attacks-against-mac-os-lion-filevault-2-encryption/#more-540

Apple admits they make computers!

Apple, announced great new features for OS X! Like facetime and app store (maybe we’ll even get some real package management). Showed off iLife 11 and Mac OS 10.7 Tiger! Many features and software available Today! Tiger is slated for summer of 2011, but facetime beta and iLife 11 are available already. Lastly, new macbook air. Thinner and more solid then every! Also, amazing battery life. I’m looking forward to getting my hands on it.