NetBooting across subnets
Being able to NetBoot from a server that’s not located on the same subnet as the Mac you’re working on can be an invaluable tool for a Mac admin. I use NetBoot all the time at my shop, both to boot new machines for setup by DeployStudio and also to boot ailing machines from NetBoot-hosted utility disks.
In my case, our network team configured our network infrastructure in order to allow my machines to NetBoot from a server located on a different subnet (in my case, the server’s located in our main datacenter.) However, not everyone has that option available. If you’re one of those folks, here’s the commands you can use to configure your Mac to boot from a specific NetBoot server located outside of the local network.
sudo bless --netboot --server bsdp://ip.address.here
This command should (hopefully) tell your Mac to boot from the default NetBoot set available from that NetBoot server.
Long version (should all be one line):
sudo bless --netboot --booter tftp://ip.address.here/NetBoot/NetBootSP0/NetBoot-Set-Name-Here.nbi/i386/booter --kernel tftp://ip.address.here/NetBoot/NetBootSP0/NetBoot-Set-Name-Here.nbi/i386/mach.macosx --kernelcache tftp://ip.address.here/NetBoot/NetBootSP0/NetBoot-Set-Name-Here.nbi/i386/x86_64/kernelcache --options "rp=nfs:ip.address.here:/private/tftpboot/NetBoot/NetBootSP0:NetBoot-Set-Name-Here.nbi/NetInstall.sparseimage"
This should work if the previous command did not, though you’ll need to know the specific NetBoot set’s name.