Run multiple instances of instadmg

[hkim823]

Just out of curiosity, but what would happen if you try to run several instances of instadmg at the same time? If I create separate folders does it work? What if I don’t and just run instaup2date and use 3 different catalog files?

[Allister Banks]

While InstaDMG should do the paranoid “right thing” by making sure it sets up all mounts randomly, the images(both temp for the dmg’s and the in-between ‘cache’ image that the actual installs go into) in use may have a hard time un-mounting, and more worrisome is the system thinking the same image is already mounted and renaming it “*-1”. The cached base image always flashes in my HardwareGrowler as “Macintosh HD”, so there may be something to this concern. The probable reason this hasn’t come up is… it’s assumed you’re going to eventually be deploying to a bunch of machines, so there’s a couple on hand. Another premise is that machine time doesn’t cost anything when it can happen without human interaction and silently(since it’s local I/O.)
It’s been hinted at that some organizations have what’s similar to a render farm, where the distribution of DMG’s and different catalog files to the workers is scripted, so multiple images can be created simultaneously.
This is mostly conjecture, but I hope it points you towards a safer solution which might work for you. Thanks,

Allister

[larkost]

As Allister alluded to the InstaDMG script is not going to handle it well if you try to run two instances at once on a computer. The mounting of the update dmgs is going to be the first problem (the current implementation naively assumes that images are not mounted already and it is not well defined what happens if something is already mounted). The second problem is that I wrap a chroot jail around a background daemon and that code is not going to work out well if run concurrently.

If you need to make concurrent images, then a image farm is probably a good solution.

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