Recommend Mac/ubuntu repair USB setup

[Tim_Johnson]

I have recently installed ubuntu 14.04 on a Mac Mini via a usb stick.
I used the instructions found here : http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-mac-osx.
I would like to prepare a rescue setup ahead of time, should a problem occur (and they have with an earlier ubuntu dual-boot on this machine).
From http://www.supergrubdisk.org/category/download/supergrub2diskdownload/super-grub2-disk-stable/, I have downloaded the
recommended hybrid iso. Currently, that is super_grub2_disk_hybrid_2.00s2.iso
Questions :
1) To create a USB bootable setup of supergrub2, would I use the same instructions as for the install stick?
2) Are there any recommendations for alternative repair setup?

I have noted that there are rescue schemes using the live install usb or cd also.
3) Can the live install USB stick mount the exisiting ubuntu partitions with write privileges?

Thanks
tim

[Tim_Johnson]

Well gee whiz. Stumped the chumps again.

[oldfred]

Are you booting with UEFI?

I do not know Mac, but my PC would not boot super grub ISO in UEFI mode.

All my repair flash drives are multiple ISO loopmount with grub2. Then I have mulitple tools on one flash drive. I have Ubuntu, gparted, parted magic, and some others.
I am finding it is a bit more difficult to UEFI boot and loopmount as ISO has to be both a loopmount configured and UEFI bootable.

[Tim_Johnson]

Hello Oldfred.

I know little about UEFI. The operative use for Mac is EFI. I've installed ubuntu successfully a couple of times using the method here
http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-mac-osx, which is a little scary because dd is scary,
and should only be used while stone-cold sober and with a full night's sleep :wink: (IMHO).

I'm going to use dd on the supergrub2 iso (converting first to .dmg) and see if that boots. I also note that I can modify files on the hard
disk if I boot with the install stick, go to "try ubuntu" and sudo an editor ...

I'll report back after I try the supergrub->dd method.

thanks for the reply ... Mac issues are new ground for me.
"Preparation is the best repair."
stay tuned.

[oldfred]

If you have a bootable Ubuntu, I consider that all the repair I usually need.
But I also like to have others, more of a belt & suspenders type I guess. Although I never have worn both. :)

[Tim_Johnson]

If you have a bootable Ubuntu, I consider that all the repair I usually need.
But I also like to have others, more of a belt & suspenders type I guess. Although I never have worn both. :)
Good analogy. Being so new to the Mac, I guess I'm going with both belt and suspenders.
Haven't go to dd'ing supergrub yet, be some time later today.
cheers

[Tim_Johnson]

I was able to burn the supergrub2 rescue disk to a thumb drive, using the dd method
referenced earlier in this thread. It boots successfully.

I wanted to make a couple of comments, since I know that not a lot of dual-booting is done with Mac computers.
1) I first attempted to make a sd card bootable - dd would not write to it. Note: I've booted slax from an sd card
before, but that was on a pc or netbook, not a mac.
2)You can select the device by holding the option key down as the computer starts up. This (I think) is called Startup Manager.
But, if I leave an external usb drive (which is used for backup) plugged in, for some reason the Mac does not "see" the bootable USB device,
so I unplug the non-bootable external USB drive before starting up.

I guess, in Oldred's terms, I have both belt and suspenders, so I'm going to mark this as solved.
cheers
tim