NetBoot runs real slow on client computers

andrew_shur
New Contributor III

I setup Netboot on a mac mini to test imaging with. Everything seemed to be working fine until I tried to image more than one mac at once. With only 5 machines it can take upwards of 30 minutes to even get to the desktop, then another 30 till Casper Imaging starts. The Server is a mac mini that hosts both the Netboot and CasperShare but I don't think that is the issue. The Netboot image was created using AutoCasperNBI and I ran the script located here https://jamfnation.jamfsoftware.com/article.html?id=369 to set up JDS too. I did notice DNS was not setup on the mac so I fixed that and tried again...still way too slow.

9 REPLIES 9

jhalvorson
Valued Contributor

Is the netboot image available over HTTP or NFS? In my testing, NFS has been faster than HTTP for OS X 10.3 to 10.9. I haven't retested it now that the server is at 10.10.

The mac mini server, is the Netboot .nbi stored on a spinning drive or SSD? Are they stored on the same drive as all of your JSS packages?

Are the client macs connecting 10/100 or gigabit all they way back to the server? Are the clients on the same switch or subnet as the netboot server?

mattware
Contributor

What's your network setup? I've found that gigabit makes the biggest difference in netboot times. Spinny disk or not.

daz_wallace
Contributor III

Hi @andrew.shur

Did your AutoCasperNBI image have the option ticked for "install modified rc.netboot file"? This creates a 2GB RAM disk on the netbooting Mac that then stores all the shadow files locally instead of on the NetBoot server. This can speed up both NetBooting and NetBoot capacity.

The other issue I had is the newer Mac Minis ship with 5400RPM drives by default. Using these for imaging / NetBoot takes an entire age. The only fix I've had for this is to upgrade the internal drives to SSDs, or move my NetBoot image store, and Distribution point to an external (Thunderbolt) RAID array, like a Pegasus unit.

I hope that helps!

Darren

andrew_shur
New Contributor III

The netboot image is over NFS. The .nbi is on a spinning drive not a SSD and the JSS packages are stored there too. The mini is hooked up to our network at 1 Gbps but the macbook's are macbook air's so they only have wireless.

I did tick the "install modified rc.netboot file" when I created the image in AutoCasperNBI. I took a look at the rc.netboot file too and noticed it did not have the updated commands shown here: https://jamfnation.jamfsoftware.com/discussion.html?id=6443#responseChild33353

So i edited the file and changed kextutil to kextload and am trying again.

bentoms
Release Candidate Programs Tester

@andrew.shur Not sure if those new steps are needed for the rc.netboot tbh.. but, Apple don't support NetBoot over Wireless.. & whilst i've done it in test/training.. I'd really not recommend it in prod.

Can you not purchase adaptors to connect the Macs to the network via a cable?

calumhunter
Valued Contributor

https://support.apple.com/kb/PH15482?locale=en_US

NetInstall and AirPort The use of AirPort wireless technology to boot clients using NetBoot is not supported by Apple.

franton
Valued Contributor III

Yeah, don't use the USB Ethernet dongles for Netboot. It's a known issue that they default down to 10Mb half duplex and makes netboot insanely slow. The gigabit thunderbolt dongles auto negotiate speed properly and don't have that issue.

andrew_shur
New Contributor III

The change to the rc.netboot file did help a lot. I'm now trying a new distribution point with an SSD. I know apple says not to use it, but a flash drive and manually installing the OS on every mac is not really the way I want to do it . I would really like something similar to PXE with our Windows computers.

Chris_Hafner
Valued Contributor II

NetBoot server I/O and speed of network are everything! Like everyone else here says, while over the air netbooting is possible, it's hellishly slow. We're imaging up to 50 MacBook (Airs) at a time in about 6-8 min using a compiled pre-stage imaging. About 15min under normal operations (Not compiling of the image and no prestaging). Thats for about 25ish Gigs. No matter what anyone says, I'll be experimenting next month with a new MacPro NetBoot server specifically to utilize it's super fast internal PCIe SSD, so I'm hoping to bump things up even further. The MacPro NetBoot Servers and DPs I run right now are hitting max on their copper enet connections (two, dual gig enet) and so the new server will be TB to either 10Gig copper or 8GPbs fiber.

With that said, it seems that most Casper installations seem to use Mac Mini's for NetBoot without too much issue so I hope things will be far better for you so long as you give up on the wireless netboot and use TB adaptors instead of USB (Which was also mentioned).