How to create a minimal OS X boot OS on a USB stick that only issues a NetBoot command

[endor-moon]

Hi Folks,

I know a number of people here have done interesting things creating small NBI files. I would like to create something that will boot the target Mac (from USB) and issue this NetBoot command and force an immediate reboot from the NetBoot server:

bless --netboot --booter tftp://10.101.118.10/NetBoot/NetBootSP0/CasperYosemite.nbi/i386/booter --kernel tftp://10.101.118.10/NetBoot/NetBootSP0/CasperYosemite.nbi/i386/mach.macosx --kernelcache tftp://10.101.118.10/NetBoot/NetBootSP0/CasperYosemite.nbi/i386/x86_64/kernelcache --options "rp=nfs:10.101.118.10:/private/tftpboot/NetBoot/NetBootSP0:CasperYosemite.nbi/NetBoot.dmg"

Due to imaging problems yesterday I have a number of iMac units that have no operating system on them. Rather than trying to boot from Internet Recovery Mode and type all this into Terminal, I was thinking it should be easy to create a minimal recovery style OS X on a USB stick whose only job is to issue the above command and reboot. I've been preparing for Casper Imaging since April and I'm now at the point where I have an image to deploy and everything is working.

I can envision a launchd plist to make this happen but the mechanics of creating a minimal OS on a USB stick to do this are a little beyond my abilities at this time.

[htse]

maybe I'm missing something, why not just startup to NetBoot directly from Startup Manager?

[endor-moon]

Because the Startup Manager isn't going to see the NetBoot server which is in another VLAN/Subnet. Hence the wordy bless command. ;)

The alternative is to bring another computer to the lab whose only job is to let the clients NetBoot to start Casper Imaging... rather time-consuming and it means moving a computer around.

[bentoms · Accepted solution]

@endor-moon or.. Use AutoCasperNBI to create a restorable DMG.

Restore that to a USB stick & boot the clients off of that & image.

[endor-moon]

Restorable DMG? Cool, I will try it. I should have known a solution was already out there. ;) Thanks.

[calumhunter]

I believe Pepijn has been working on a raspberry pi version of BSDPy. With the API version you can have your actual NBI hosted on a webserver somewhere, yet the tftp booter lives on the pi, so the clients 'see' the NBI on the pi, but they get directected to the webserver with the NBI for actual booting
Simply plug the pi into vlan/subnet and option boot your heart away.

have you tried that bless command on 10.11 betas?

[endor-moon]

I haven't done much with the 10.11 betas just yet, no. "see the NBI on the pi" has a nice ring to it, though. ;)

[calumhunter]

I would recommend you try out the betas and submit bug reports if required...

this might be relevant to your interested http://www.openradar.me/21310286t

[endor-moon]

Thanks for the link, calumhunter, I will consider it.

[endor-moon]

Thanks @bentoms, your suggestion works like a charm.