JAMF netboot appliance - advertise multiple netboot images across VLANs?

Valued Contributor II

I googled and found this thread on MacEnt regarding a few posts about the Netboot appliance having issues across VLANs with helper addresses. I assume this is still an issue? How are people using the appliance if so in larger environments where having a netboot appliance in same VLAN as clients isn't possible?


Also, I believe there was also some talk at 2013 JNUC that with the netboot appliance as it is now (I guess if on same VLAN or if you can get helpers to work), you can't advertise multiple netboot images when using helper addresses (i.e. tech holds down option key and sees 2 netboot images and/or 2 netboot images also appear in startup pain). Is that still correct?

2 years ago we had to host 2 netboot images because 2012 Airs wouldn't work on previous netboot images, but older hardware wouldn't work on the 2012 Air netboot image. The 2013 Air netboot images worked with old hardware, so it wasn't an issue for us this year, but I am concerned we'll need this functionality in the future as we always seem to do a mass purchase right as new Macbook hardware is released (and before a combo update comes out).

Have others figured out advertising multiple netboot appliances across vlans? I think at JNUC someone mentioned some bless commands techs could do, but that may be beyond their scope and/or waste of time when imaging thousands of computers in few weeks like we do.

Thanks in advance. Trying to figure out if I really need to buy some minis just for easy netboot to work with helpers.


Contributor II

Thanks for bringing this back up @CasperSally][/url][/url. There's an older thread here:


I used the info posted there and from that ME thread to generate thatreallycomplicatedblesscommand below. Ultimately though that does us no good as a means of mass deploying bare metal machines from Apple, which was what I was really after.

I would be happy to compare notes with others on this, but in our testing the clients never auto discover the NetSUS server, even when the appropriate helper address is in place. Our PXE-boot Windows clients across the same subnets work fine. The explanation of an updated firmware that forces a smaller block size by Reliant off the ME thread is the only explanation I found as to why this issue has not yet been resolved. Here's the bless command I've used successfully to force NetBooting for live clients:


#### NetBootSet.sh
#### This is a script that prints out the parameters that are passed to it
#### Casper needs the first 3 parameters of a script to be predefined
#### The first is the mount point of the target drive, the second is the 
#### computer name and the third is the username. The next 8 parameters can
#### be specified by the user. Labels for those parameters can be entered
#### in Casper Admin or the Casper Admin function of the JAMF Software Server
#### Happy Scripting!

#### Read in the parameters
BootChoice="$4"         # specific either NetBoot or NetInstall
BootImage="$5"          # specify specific NetBoot/Install image off server

bless --verbose --netboot --booter tftp://netboot.server.com/"$BootImage".nbi/i386/booter --kernelcache tftp://netboot.server.com/"$BootImage".nbi/i386/x86_64/kernelcache --options 'rp=nfs:netboot.server.com:/srv/NetBoot/NetBootSP0:'$BootImage'.nbi/'$BootChoice.dmg'' --nextonly

exit 0

Valued Contributor II

Thanks for the reply @clifhirtle.

It's disappointing I guess the consensus is with the netboot appliance, there's no way to host multiple netboot files that are available both via option key and startup pane for mass deployments... and helper addresses even further complicates things.


I've tried to set up a Mac Netboot server AND use the Casper Netboot server on the same VLAN unsuccessfully. If I turn off one or the other, the opposite works, but hosting both at the same time fails to the Apple (priority and helper statements point to the Jamf Netboot).

I'm trying to research and learn more about using the Bless command to select a different NBI from the Jamf server, so it will be able to host more, but so far, I've been unsuccessful.

For now, I must have my Apple and Jamf NetBoot on different VLANs.

Valued Contributor II

@chuck3000 I might be wrong on this, but I don't think you can host two Apple NetBoot servers on the same VLAN anyway regardless of NetSUS or Apple server. They would be broadcasting the same traffic I would think something like having two DHCP servers on the same network. I tested this in our lab and I could see both servers NBI sets, but nothing would boot until I turned one off.

Release Candidate Programs Tester

If you change the NetBoot Images index to over 4096, you should be able to load balance it & host it on multiple servers.

As per:

In the image index field, type an Image ID.
To create an image that is unique to this server, choose an ID in the range 1-4095.
To create one of several identical images to be stored on different servers for load balancing, use an ID in the range 4096-65535.
Multiple images of the same type with the same ID in this range are listed as a single image in a client's Startup Disk preferences panel.


We do this with our 10.9 servers, I imagine it would work with NetSUS & Apple NetBoot servers.

Contributor II

We ran into an issue when I spun up a NetSUS box and turned on the NetBoot service. We opened a support ticket with Apple. I don't have the details in front of me so I'm going off memory. But in short, according the Apple Professional Services, the JAMF appliance was broadcasting itself as the "authoritative device" or something in regards to priority. And even choosing the Apple NetBoot server it would fail. But I believe we've had more than one Apple NetBoot server on a subnet with success.

As for hosting multiple NBI's I've got one running with several. It's a v1.02 NetSUS that does NFS sharing. I've got a package that sets the bless command and can boot a system from any of the hosted NBI's. But the device will only support one "default". If you're interested in the package let me know and I can share it. It was built using Bombich's NBAS (NetBoot Across Subnet Utility) and tweaked to match the share of the NetSUS.

New Contributor

I've been trying to hack a JAMF netsus to host and broadcast 2 netboot images.

I've managed to get most of the way there by looking at the DHCPD file that ships with the Netsus and the following guide has been very helpful: http://bennettp123.com/mirror-brandon.penglasee.net

Unfortunately this solution doesn't broadcast the netboot images to "Startup Disk" in System Preferences, which is really an invaluable feature for our school.

@Brad_G does your solution broadcast to the system preferences?

Contributor II

No, I only get the standard single "default". At the 2013 user conference during a session with Eric Krause someone in the audience described how they were able to advertise multiple netboot images from the NetSUS but I don't know if they've posted anything here (I couldn't find it if they did).

I simply use different packages or scripts with the appropriate "bless" command for the NetBoot set I want the client to use.

Sorry couldn't be of more help.


I would like to see the package/script that Brad_G is using. How/Where are using this package in order to control which net boot image is used?