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I need some mac partition help..

I want to be able to create a Master partition (The one I am using now) and a slave partition (of about 50GB for other uses). This is for a pure security reason. I want to have a place to do some stuff that I would not generally do on my main partition (like run applications from unknown), or do things with the filesystem in experimentation.

I have several concerns/problems

It appears that each partition is equal. Meaning the 2nd can write to the 1st and visa versa. = Bad. I want the first to be able to write to the second (but not really required), and the 2nd to be impossible to write to the first. I know this is possible with a windows dual boot, but i'm not sure if/how it is possible with a partition of Mac os.

I would like them to have seperate file systems. Once again for experimentation and security-type reasons.

I want to use Mac OS for this. Windows is generally unacceptable, I try to avoid it if possible. Plus, the type of applications I wish to run and experimentation I wish to do is primarily unix/mac based. So I have a question. - Is what I want possible? - If so, how?

My computers is: - iMac running 10.8, 2011 version

I greatly appreciate the feedback and help.

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migrated from Dec 15 '12 at 8:04

This question came from our site for professional and enthusiast programmers.

Use a virtual machine for running the untrusted code. – user7541 Dec 15 '12 at 2:07

I’m not sure why you’re calling it a master/slave partition – that would suggest some kind of replication or backup system?

It sounds like what you’re asking is how to have multiple bootable partitions on OS X, and how to make sure they can’t touch each other?

Dual Booting OS X

Use Disk Utility to make a second partition.

Find the OS X installer (may have to download from the App Store), and tell it to install OS X onto the second partition.

When that’s all done, hold option when the Mac boots to choose which partition to boot from.

Mounting partitions as read-only

To change how partitions are mounted, create an /etc/fstab file, as is standard for Unix systems. You can/should use the vifs(8) program to do this.

Add a line like: (where myPartitionsUUID is found in Disk Utility (File > Get Info))

UUID=myPartitionsUUID  /Volumes/OtherPartition  hfs  r,auto

Here’s a link that explains this a little more:

Note: I haven’t actually ever tried this partition mounting bit, but I’m reasonable confident it’d work.

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