Macintosh Booting Options - Part Deux
In the first part of my story on Mac Booting Options, we went over the startup disk selection options and some of the details regarding booting the Macs with “New World” ROMs. Now we move to some of the lesser known options that can prove useful when troubleshooting Macs.
Two special modes for booting up Mac OS X machines today include single-user and verbose modes. To enable these modes, hold down either the -s or -v keys on the keyboard upon booting your Macintosh to enter single-user or verbose modes respectively.
Single-user mode is useful for running disk repair routines that need uninterrupted access to the hard drive. Single-user mode gives the user of the Mac root access privileges, which are necessary for some diagnostic and repair routines. The most common command to run for checking the disk is the following:
fsck -y
This command will do a file system consistency check on the UNIX file system run by the newer Mac OS X machines. It should be noted that the file system Macs use is normally a journaled file system format and thus fsck is not required to be run very often.
Verbose mode allows your Mac to boot up as if you were watching a Linux box startup. You see the drivers load, services startup and perhaps more importantly you can look for oddities or errors in the boot process. You will need to hold down both the Command and V keys on bootup to use verbose mode.
Finally, to protect your Mac from someone hacking it on bootup, you can place a password on the Open Firmware of PowerPC Macs and the EFI (Extensible Firmware Interface) of Intel Macs. Computers as old as G3 iMacs with slot loading CD/DVD drives can use firmware passwords. The firmware password will block attempts to bypass startup from the hard disk by using -c, -n, -t, -v, -s flags discussed in earlier sections and articles on Mac boot options.
In order to activate firmware password protection, you must download and/or use the correct program for your version of OS X. There is an Open Firmware Password application that can be downloaded for Mac OS X 10.3.x and earlier, while new versions of Mac OS X come with the application installed in the Utilities folder on their Macs.
The application is self explanatory and once your password is enabled, you have added a hardware layer of protection to people who might otherwise crack your Mac’s security shell. Here is to security!
This article was written by Perry Lund on Monday, March 24, 2008. Permalink.