Hi Brian,
Before starting anything, I assume that you have at least one full up-to date backup of your existing system! I think you need to be a bit clearer on what you are trying to do and why. Some thoughts: If you just want to have a temporary external USB boot drive then you do not need a large USB drive. When I decided to upgrade 3 computers to El Capitan I created a bootable USB flash drive with just the El Capitan installer on it. The actual USB drive is only 32GB capacity and only 6.2GB of that is used for the El Capitan Install app. This drive allowed me to boot-up the computer and erase/reformat the internal hard drive and do a clean install of El Capitan. Obviously this approach requires that I have already got my original system and user data backed up elsewhere. Then you need to decide what apps and data you want/need to migrate over. When you say "I would like to wipe MacBook Air’s drive and re-establish El Capitan on it. (Why I need to do this is a longer story)" - the "WHY" will probably have a bearing on "HOW" you should go about it! For example: If your existing setup is all working fine and you just want/need to reformat the internal drive (say change the partition scheme) then you would probably just clone the existing system drive/partition to an external drive, reformat the internal drive and then clone back from the external drive to your new internal target. On the other hand, if your reason(s) to wipe the drive and re-install the OS is down to some perceived problems with the existing set-up then just moving the existing set-up to the external drive and then back again will most likely retain the problem! The nature of any existing problem would, most likely, tend to drive the best approach to reinstalling the system and user data - is the problem likely down to system corruption or user data/preference corruption? I'm not sure how helpful all that is but my experience has definitely been that more time spent analysing and planning BEFORE you dive in will often save problems down the track and save time in the long run. HTH Cheers Neil -- Neil R. Houghton Albany, Western Australia Tel: +61 8 9841 6063 Email: n...@possumology.com -----Original Message----- From: <wamug.org.au-wamug-boun...@lists.wamug.org.au> on behalf of Brian W Scott <scot...@exemail.com.au> Reply-To: WAMUG <wamug@wamug.org.au> Date: Saturday, 29 June 2019 at 17:23 To: WAMUG <wamug@wamug.org.au> Subject: Re: Is it possible to have an External USB boot drive? Hi, I found I could do it with the Recovery Disk/Partition. But it’s complaining that the 4TB drive I’m trying to put it on is not big enough. I suspected it must using the MacBook Air drive to store stuff so I’ve made some room on it and will try again tomorrow. 208.95 GB should do it I guess. At one time it said it had About 1,102,053,030 hrs 22 mins to go. (That’s 125,722 average Gregorian years) But about a minute later it continued on to it’s next activity. > On 29 Jun 2019, at 1:34 pm, Brian W Scott <scot...@exemail.com.au> wrote: > > Hi, > > I have a MacBook Air 13 inch, Mid 2011 with Mac OS 10.7.5 El Capitan 10.11.6 on it. > > I would like to wipe MacBook Air’s drive and re-establish El Capitan on it. (Why I need to do this is a longer story) > > I have a 4TB USB powered by the USB port it doesn’t have a power supply. > > I was thinking I could use it as an external boot drive while I deal with the MacBook Air’s drive. > > If it is possible to do the above could someone please point me to some instructions for getting this done. > > Thank you, > > Brian Scott > > -- The WA Macintosh User Group Mailing List -- > Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> > Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> > Settings & Unsubscribe - <http://lists.wamug.org.au/listinfo/wamug.org.au-wamug> -- The WA Macintosh User Group Mailing List -- Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> Settings & Unsubscribe - <http://lists.wamug.org.au/listinfo/wamug.org.au-wamug>
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