Enhancement: Reduce DMG size further by using .sparseimage about autocaspernbi

[macmule]

Hi Hunty1,

I've been thinking about that since I saw that CNIC does it, the below is from that.. I may give it a go to see how much is saved.. the only issue is that then booting can be slower as it needs to decompress.

But something for me to look at.

https://github.com/jamf/CasperNetInstallCreator/blob/master/CasperNetInstallCreator/Creator.m#L220

[calum-github]

Just a quick update, in my very limited testing, i've found that the sparseimage is about 15 seconds faster to boot than the netboot.reduced.dmg. I ran 5 tests of the sparse and 5 tests of the normal dmg and averaged out the times (they were all within about 3-5 seconds) Could just be me. But interesting result

[macmule]

Hi Hunty1,

As mentioned on twitter, I had made some changes to AutoCasperNBI to move to sparse images.. only to find that JAMFs NetSUS appliance currently doesn't support sparse images without some modification (jamf/NetSUS#53).

AutoCasperNBI generated NBI will be mostly hosted on an OSX Server or NetSUS, as such I'm going to leave the image format as a DMG until the above issue is fixed.

I know there are workarounds to enable sparse image support in NetSUS (http://derflounder.wordpress.com/2012/02/07/modifying-jamfs-netsus-to-host-deploystudio-netboot-boot-sets/), but I am cautious of a) the additional support overhead in this approach (too myself) & b) in moving to sparse images a large amount of AutoCasperNBI had to be re-written, too much to allow user selection of disk format.

It's still a very good idea, & one i'll revisit once the NetSUS supports sparse images.

[calum-github]

Roger that. I must admit I did not do any testing with NetSUS, I only use BSDPy these days. Considering the app is called Auto_CASPER_NBI, really should consider who the target market is and what NetBoot Server they are going to use and maximise compatibility for that. I'm probably an outlier... until the people see the light and switch to bsdpy ;) Appreciate your efforts especially considering its AppleScript!
Lets hope that NetSUS gets updated to support sparseimages and/or preserve symlinks when NBI's are uploaded via samba/netatalk

Cheers

[calum-github]

Just for my own curiosity I grabbed the NetSUS 3.0.2 OVA

Used the beta of autocaspernbi you sent me to create an NBI with a sparseimage
I simply renamed NetBoot.reduced.sparseimage to NetBoot.reduced.dmg
Uploaded the .nbi folder to the NetSUS and was able to successfully netboot client machines.

[macmule]

In 1.1.5

[macmule]

To expand apon the above, a sparseimage is now created.

As NetSUS doesn't support sparseimages, the NBI is renamed .dmg if "Hosted on NetSUS" is ticked.