Old Macmini ignores ownership on external HD's, new Macmini does not.

Question

Hi - my old Mac mini has a couple of external HD's set to "ignore ownership on this volume", as they are just storing personal files, one backing up the other nightly. I transferred them to a new Macmini, only to find my backup software won't update from one external to the other (permissions type error messages), and the "ignore ownership on this volume" checkboxes on each are not checked, and greyed out.
I've tranferred the HD's back to the old Macmini, and presto the "ignore ownership on this volume" boxes are now checked again. How can I make this behaviour transfer safely to the new comp?

Answer 1

Thank you! I haven't yet dared try this, but I've found the following info that explains those commands in a fashion even I could understand - I take it this will work for all enclosed folders too? -
chmod stands for "Change Mode".
The numbers part is a little more complicated.... "777" is three numbers..to be nerdy and specific.. it is three 3 digit binary (base 2) numbers converted into three 1 digit octal (base 8) numbers.
The first number stands for "user", the second group stands for "group" and the final number stands for "other". There are three possible things that can be done with a file: read, write, and execute.. Here is a little reference:
execute = 001 in binary = 1 in octal
write = 010 in binary = 2 in octal
read = 100 in binary = 4 in octal
So where does the 7 come from?
7 in binary = 111 in decimal = read, write, execute
So you get:
read write execute = 111 = 1 + 2 + 4 = 7
read write no execute = 110 = 4 + 2 = 6
read no write execute = 101 = 4 + 1 = 5
read no write no execute = 100 = 4
no read write execute = 011 = 2 + 1 = 3
no read write no execute = 010 = 2
no read no write execute = 001 = 1
no read no write no execute = 000 = 0
<http://www.websitebabble.com/uploading-files-ftp/1667-what-chmod-777-a.html>
I'll have a go in the next few days (will need to switch the HD's back to the new comp first etc) when I'm feeling brave.
Message was edited by: midwich
Message was edited by: midwich
Message was edited by: midwich