arrividerci wrote:
You refer to an Installation Kit as something that must be downloaded using another Mac. It sounds like you are saying that the actual files that will be used to perform the installation, which includes being able to boot from the media, can be created by any (?) Mac. I suspect the requirement for the Mac has to do with insuring the media is formatted with a suitable file system that is bootable.
Please do not carry across your assumptions of Windows, nor (most of) your experiences managing and maintaining Windows.
That path quite often leads to confusion and frustration, as OS X is very different than Windows.
As for the ability to swap disk around with OS X... That works. While there are some old installer DVD disks that were tied to specific systems and there were some retail DVD disks that can be installed on any Mac, but bootable disks and bootable USB flash disks will work across all Mac systems that are supported by the OS X version that's present on the disk you're booting.
Contrast this with what you're likely familiar with from Windows: Microsoft ties a specific Windows installation to a specific x86, Alpha, PowerPC, MIPS R4000, or whatever other box was booting Windows. Apple does not tie an OS X installation to a specific Mac, and the OS X software installations all contain all of the necessary drivers needed to boot and run, for any Mac supported by the specific version of OS X.
You do need to watch your App Store purchases and limits and the Apple Terms and Conditions, but that's pretty much the limit here.
Can you provide a reference to the source for downloading the Installation Kit.
That's in the linked articles, and it's been discussed in various other replies here — launch the App Store.app and download the Yosemite installer. This is the same kit that was referenced earlier as one of the paths to "nuke and pave" this system.
Something I would contemplate doing after a successful recovery has been completed which will include restoring the user selected applications is to create the necessary media for reacting more expeditiously to the need to make a restoration. Is there a way to create some kind of system image once a reliable and trusted system is operational that can be used to make a complete restoration?
Backups via Time Machine or other tools. Again, you are carrying over Windows. Time Machine is built in, multiple targets are supported, and operations are transparent. Could you spend your time creating a disk image and storing it somewhere else, and manually maintaining the sequencing and the rest of an "enterprise" backup — "enterprise" meaning awkward, expensive, buggy and problematic — sure. But it'll be easier to do what was suggested — use createinstallmedia to generate bootable media — which creates what you are asking for, with the most current bits available from Apple.
With respect to DVD, I only meant that as an example. The unalterable property of certain DVD formats is desirable for such files. Also, it tends to be an inexpensive way to store things you put in a drawer with the hope that you will never need to use them. However, being able to store the media offline, as with any removable media, provides the kind of protection that I'm seeking. The reference to the "createinstallmedia" command reads like part of the function performed by this software is to download the necessary files. Might that be correct? If so this is worth pursuing.
My experience with DVD media and DVD drives is apparently far less rosy than yours. I store a couple of bootable USB disks offline — created with createinstallmedia — and try to remember to update those as the new OS X versions and new releases are shipped.
All that written, OS X is itself largely uninteresting here. The Mac itself is also uninteresting here, too. Why uninteresting? Because it is your data and your local applications that are paramount. You can download a new copy of Yosemite or of the upcoming El Capitan and install it using the sequences cited here. Your data is far more difficult to replace and far more precious — which gets into off-line and off-site backups, device encryption, and related discussions. Malware is secondary, and is far less of an issue than on Windows. Absent the traditionally security-problematic Adobe Flash and Oracle Java tools and weak or exposed passwords, the "easiest" way for folks to get malware onto your system is to trick you into installing it.
For more information... I've written up the sequence used to recover a server from a breach, assuming that rolling in a pre-breach backup is not feasible. US NSA and Apple have some guidelines, as well; when last I checked, the Apple guides were dated, and do not reflect newer changes to OS X, including Xprotect, file quarantines, and Gatekeeper, as well as the upcoming system integrity protection changes with El Capitan.