Mass deployment - Netboot imaging

@bwiessne Around 30 Macs can be NetBooted off of a single netboot server if the NBI's rc.netboot is amended, 10 if not.

Your imaging time will slow too.. though & it really depends on what you're imaging & other considerations.. so YMMV.

Maybe try 30 @ once & see.

Id agree with that estimate as well. Between 15-30 work well at a time off a single netboot server over a gigabit connection. I end up also compiling the image compressed as well. At one point I tried to get multicasting to work to speed things up, but this is an old feature with very little support.

We use a new macpro with 6 cores and 64gb aggregated ethernet ports for casper and a seperate mac mini server netboot server with dual ssds.

Gabe Shackney
Princeton Public Schools

With a gig link to the imaging switch, I've found it pretty pointless to do any more than 10 at a time since you're effectively down to 100 megs per unit and then there's disk saturation on the server. Get too many devices running at once, you'll just end up having more downtime than it's worth. So I'd guess about 20 in your case.

We image around 700-800 MacBook Pros (the optical drive model with spinning HD) every August for distribution to our students. NetBoot was just too slow for us so we use 20 SSD Thunderbolt drives and offline imaging. We're able to image the fleet in about 3 days. There's an investment in the SSD drives but we've used them for a couple of years now and they've paid for themselves in time saved.

It may be worth it to try target imaging and cache the images locally on the machines while doing the NetBoot. Could save you tons of hours.

I would say that 30 at once is the upper limit although it will also depend on whats being deployed in your configuration. The speed of the distribution point is really important. We had some real performance issues recently with one client so I tested:

• Netboot and AFP DP
• Local disk and AFP DP
• Local disk and local DP

Taking out netboot didn't really speed things up much at all. Moving the DP to a local (external thunderbolt) disk made a massive difference.

Not sure what your disk configuration is in the Mac Pro but if you can have 3 disks as RAID 5 that will help ensure they aren't maxed out.

We've had to deploy a new batch of Macs at one of our sites (350) recently and tested deploying with LaCie thunderbolt SSD drives. The deployment time wen't from 2 hours per Mac to 10 mins. The overhead of purchasing the drives and a bit more manual involvement was made up for by the speed of deployment and we were left with a bunch of drives that we could use to re-image very quickly should we need to.

Multicasting is BAD, FYI.

We can run ~50 at a time over gigabit. That said, during primary imaging (once a year) our NetBoot server in this case also hosts the DP for the PreStaged image, on an internal HW RAID (2011-MacPro). So, don't expect a MacMini hosting a DP on standard HDDs to do that. That said, you'll probably never manage to get that many Airs imaging at the same time if you use a compressed image. The damned things will image so fast you won't be able to get 50 started and running all at once before the first ones are finishing. We push ~24 Gig images to those units in about 5 min, power on to login screen.

With the right equipment two people could get through those in a day with the right workflow and enough Gigabit ethernet adaptors. That said try NOT to promise things like that. I almost had it bite me in the arse after a "late" network change dramatically affected NetBoot imaging speeds one year and we had no emergency time built in anywhere. Fortunately, we pulled it off but it was rough. Those were spinning platter speeds though, not SSDs.

for one client i built an imaging rig on a trolley
basically an old xserve raid 0 across 3x 15k sas drives
the server was a netboot server and casper DP
I LACP'd the 4 gig-e ports off the xserve(2 on board and 2 from pci card) to a high end 48 port gig switch
managed to image 300 macbook airs via thunderbolt-gigabit ethernet adapters in 2 days by myself. running 20 machines at a time, image was autodmg base and then installing packages via policies for adobe cs 6, iwork, ilife, office all the regular apps for edu, so it was quite a large image in the end.

got some decent throughput out of the old 2008 xserve though

We had netsus servers(old lab PCs) on each switch where we imaged. Each switch had its own vlan and we used that and prestage imaging to do 120 at once. Each table had 20 and a netsus/ distro point. Really worked well for us and naming them correctly.

I tend to find that 10-20 at once is more than enough if you're doing it by yourself, how many you want netbooted at once depends on how many people you have, for instance if you have 5 people working on it to get it done ASAP netboot may be okay for up to 30, depending on your infrastructure, then you could have another 20 going over target mode imaging for example.

Ahhh, see, these are the stories I love! @calumhunter @peineke @Matt.Sim.

To add some clarification to our imaging process we no longer mass image units "for" our students. They do it themselves in a PreStage during orientation (~365 students). They rotate into an imaging center (lecture hall setup for the purpose on day 1), plug in and hold 'n'. Once they get to the login screen they log in and enrollment is verified. Takes less than a day and it's completely hands off. That only leaves me with about 100-200 units to image for the Staff/Faculty in a single shot and we usually leave it to an intern for an afternoon rpoject.

So, while our system is tested to run 50 in a go it's almost never fully utilized. If anyone is interested I have load balanced NetBoot servers to run at higher numbers but the speed is about the same regardless.

@Chris_Hafner How many netboot servers are you running at one time? Are you doing an aggregated link?

What steps should we take to be able to netboot 50 at a time?

Thank you.

I run a max limit of 50 for a single NetBoot server. That particular box is a Mid-2010 MacPro running an aggregated ethernet link and serving NetBoot (and DP) services from an internal HW RAID (Striped-0). The RAID if you can call it that, runs off an Areca 1880ix card with 3 15k7 cheetah drives.I've never had an issue with that number so long as the network is up t the task. If things get routed all over a large network then it's all crap. During our 'time sensitive' imaging events I usually turn NetBoot on, on a second identical MacPro that contains an identical (Properly indexed) .nbi. This would allow me to theoretically handle up to 100 (That's the default limit on OS X NetBoot services).

As for steps. Make damned sure that your network is up to the task. Otherwise, it's pretty simple. High speed I/O, plenty of RAM and a proper network path. Heck, I'd even run it on its own subnet if you could. I don't, but it's not a bad idea.

P.S> I pay a LOT of attention to my .NBIs as well. I've tended to make my own up until this year. Now I'm using AutoCasperNBI for my standard NetBoot environment and CasperNetinstallCreator for a quick .NBI that runs in RAMDisk.

@calumhunter Just because you posted your pic I had to shoot this over. These are my two current MacPros (2010) running. This is actually low load. Just a few units imaging this morning and and few base OS .dmgs uploading... and well, the rest of my policies. The white line is our JSS web server (and secondary DP) and the blue line is my primary NetBoot (only one on at the moment) and primary DP.

However, I'm going to be building a new completely flash based MacPro for single server HS NetBoot+DP for my September Pre-Stage. That new unit will have either dual 10GBPs connections to our fiber switch or direct fiber connections (All via TB). we're still debating. We also just ran a new fiber drop to our main imaging area and will bring a suitable edge switch in just for primary student imaging. I'm hoping to make these numbers look tiny in comparison.

@Chris_Hafner Do you have any documentation on the 10GBPs connection fiber to Thunderbolt?

Nothing beyond what Apple has. Basically, I've budgeted for either solution via Apple, and will re-evaluate just before I place the order in June. Basically, I'm just trying to prep the next server to handle whatever I throw at it for it's intended 4ish year lifespan as a primary. So, with that said I'm really just watching the PROMISESanLink2 adaptors. I haven't yet been able to dive in and do the proper research to see if I can bond more than one without causing issues. It's all about overall I/O so there's only so much I can do with a single SSD that will be operating the OS, NetBoot and DP.

http://www.promise.com/Products/SANLink

And... just because.