Solved

example code of Unix bless command

Posted on 2014-09-28
2
270 Views
Last Modified: 2014-10-01
Need Unix example code for using “bless”.

Present situation
******************
Apple downloads a “Mavericks” operating system to my 128-GB thumb drive.

This download takes anywhere from 5-hours to 14-hours

Resulting thumb drive is bootable, no problem, happy user.

I then create a backup of the entire thumb drive using Apple’s “Time Machine” application.

Problem:   Restored thumb drive is no longer bootable, therefore is useless.

This ONLY happens with the physically small thumb drives.

Keep in mind that when Apple downloads their Mavericks OS to the same thumb drive, the drive is bootable, no problem.   If Apple can force the thumb drive to be bootable, then we should be able to also.

If instead of a thumb drive, I use a larger SSD, the physically larger drive does NOT lose its ability to be bootable after being restored by a Time Machine backup.


Question
**********
Is it possible to use Unix “bless” to restore a thumb drives bootable characteristic?

My Unix knowledge is extremely weak, so the “man bless” command is gibberish to me.

I know how to use a few Unix commands, like:   diskutil list
and even:  diskutil partitionDisk disk1 2 JHFS+ MAIL-2 42949672960b JHFS+ UNUSED_AA 1048576b


Could some expert please supply some example code of a bless command?

I might be able to puzzle out how to use “bless” from the example code.

Possibly some example like:     bless  disk2  MyThumb  setBoot

( I don’t have the nerve to try the above example, for fear of omitting essential info’ )


My Setup
**********
MacBook Pro computer running latest “Mavericks” OS.

Bootable external drives, both the spinning mechanical types and the SSD types.
0
Comment
Question by:SuperSenile
2 Comments
 
LVL 28

Accepted Solution

by:
serialband earned 500 total points
ID: 40353453
Near the end of the manpage, you'll see some examples.


man bless
<snip>

   FOLDER MODE
     To bless a volume with only Mac OS X or Darwin, and create the BootX and boot.efi files as needed:

           bless --folder "/Volumes/Mac OS X/System/Library/CoreServices" --bootinfo --bootefi

   MOUNT MODE
     To set a volume containing either Mac OS 9 and Mac OS X to be the active volume:

           bless --mount "/Volumes/Mac OS" --setBoot

   NETBOOT MODE
     To set the system to NetBoot and broadcast for an available server:

           bless --netboot --server bsdp://255.255.255.255

   INFO MODE
     To gather information about the currently selected volume (as determined by the firmware), suitable for
     piping to a program capable of parsing Property Lists:

           bless --info --plist

Open in new window



Here's a couple of sites with examples as well.

http://www.egg-tech.com/mac_backup/
http://www.projectosx.com/forum/index.php?showtopic=3171
0
 

Author Closing Comment

by:SuperSenile
ID: 40355203
Thanks again serialband,  I appreciate the help.

SuperSenile -
0

Featured Post

Best Practices: Disaster Recovery Testing

Besides backup, any IT division should have a disaster recovery plan. You will find a few tips below relating to the development of such a plan and to what issues one should pay special attention in the course of backup planning.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In this article we discuss how to recover the missing Outlook 2011 for Mac data like Emails and Contacts manually.
The Delta outage: 650 cancelled flights, more than 1200 delayed flights, thousands of frustrated customers, tens of millions of dollars in damages – plus untold reputational damage to one of the world’s most trusted airlines. All due to a catastroph…
This tutorial will walk an individual through locating and launching the BEUtility application to properly change the service account username and\or password in situation where it may be necessary or where the password has been inadvertently change…
This tutorial will walk an individual through the process of installing of Data Protection Manager on a server running Windows Server 2012 R2, including the prerequisites. Microsoft .Net 3.5 is required. To install this feature, go to Server Manager…

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question