My bumpy journey from Windows to OSX and Parallels - a tale of backups

NOTE - Update at the bottom of this post - added on 28 Sep

I though that I would document my journey from Windows to OSX and Parallels for two reasons - to allow any experts to identify if I have done anything wrong and allow them to point it out, and to help others going through the same process.

3 months ago I was a 15 year Windows man, with lots of Windows-based legacy data and applications. On my retirement I decided that I wanted to keep my programming brain active, so chose to write an iOS-based App. I researched this, and decided to buy an iMAC (250GB storage) and run a virtual Widows machine to take all my Windows collateral. I chose Parallels, and used their ‘Switch to Mac Essentials’ application.

The installation went pretty smoothly, and established the VM with all my Windows stuff (circa 170GB). Backup onto a 2TB USB drive using Time Machine. Plenty of room, I thought

Early on I got a little twitchy about the Windows backup, so I got a Windows formatted USB drive and, using Acronis running in the VM, established a file level daily and weekly differential backup. That works fine, and I can see the files as I am used to in Windows. Note that Acronis to not officially support this, so I am keeping a close eye on things.

Had some problems with getting the drives recognised by the right OS, but, with Parallels help, got that sorted.

Sat back and though - great - all done.

Then Time Machine started to complain about lack of space, and deleting stuff from two weeks ago. I scratched my head, and decided that, even though TM was doing a differential backup, because my VM is a single file in OSX, every time I did anything in Windows, TM re-copied all of the 170GB as a differential copy.

I contacted Parallels, and spend many hours trying to understand how to avoid this problem. There seemed to be an approach using Smart Guard and snapshots, but no-one could explain how it worked, and as all my work still resided in the Windows environment, I didn’t want to risk it. So, this is the solution I have arrived at:

1. Parallels .pvm file located on a 250GB SSD linked through USB port to iMAC. Parallels pointed to that as main VM. Performant enough, I find

2. Acronis running on VM backing up Windows to Windows formatted, USB connected, HDD. Daily and weekly differential

3. Time Machine backing up a now much smaller OSX, now the .pvm is not there​

The only thing I am now doing is, because I suspect that my old version of Windows was a bit ‘iffy’, I am building a brand new Windows VM on Parallels, and will slowly migrate everything to it. I should finish up with a nice, clean and fast version of Windows, and will delete the old one.

I also moved my pictures from Window to OSX, which reduced the Windows storage size. I expect that I will also move more and more of my work to OSX, but lots of my history is based on Office. amnd do not want to risk that. So there will always be a place for Windows.

That is my story so far - if there are any experts out there who feel that there are some monsters around that I have not spotted, please tell me.

With many thanks to Honza - see below - my adventure continues:
Honza suggested that if I move my main storage of my Windows files from the VM to MAC storage I would resolve many of these backup issues. So - I am now experimenting with this and am moving some of my less key files to be MAC based, and am configuring Parallels to "Share MAC user folders with Windows". This should allow me to move these files onto an area within Documents on the MAC and access them from Windows. I have created a 'Windows documents' sub folder on the MAC, and, for the moment, I am storing them there.

This should, when all Windows files are moved to MAC storage, significantly reduce the size of the VM and allow me to use Time Machine fully

The big jump will be when (and if) I move my Outlook .pst files there - I would need to be very certain that this will be safe and work. I also use Nelson Email Organiser (NEO) to manage my Outlook mail - this is one of the key things that I cannot afford to loose - and it does not have a MAC based version.

I will keep you posted

 

Hello JohnCa,

the problem between TimeMachine and Parallels VM (or any other VM for that matter) is well known and I assumed documented. Basically, since Parallels hd is basically large binary file, TM every time the VM changes must copy it whole and runs out of any space really quickly.
Supposedly there are some solutions, but I am still dubious about all of them.
Here is my solution:
1. ALL data (my files, anything, which contains my work, my music, pictures, anything I consider "mine" - simply is not system or application/program) belong onto Mac, where it is well backuped by TM. This takes care of the important stuff... This keeps me "safe". By the way, I have TWO time Machnie disks, located at different places. I have had TM disks failed few times, so two gives much more reliability.

2. So my VMs contain only system and applications. Keeps them small and minimizes also need to recompress VM disks, which will grow with time as you delete files. VMs cannot shrink the virtual drives by themselves and actually, only Windows VM can do it easily.
Therefore, I do routine, may be weekly copy (two rotating copies, actually) of VM onto external drive (must be mac formatted). You can simply drag and drop VM on external drive and it will copy without problems. It will even run from there
This can even be done with simple reminder to myself. If VM contains only applications, weekly (even biweekly) backup is perfectly fine. Of course, backup before any major update to OS (and after success has been verified) is also useful and smart.

Now that works in most cases.

In one case I have large desktop with enough space, that I created second hard drive, formatted ntfs, installed Windows there through Bootcamp and run the Windows off real hard drive. Works fine, but since the TM is _the_simple_best_ backup system I have ever used, all data reside still on Mac and nothing really changed. Except the backup of Windows is now really only Windows matter. But not much easier, actually...

NOTE: if the TM disk is large enough, you can use that disk for the copies of the Parallels VM. I do. Works fine.
Honza

Oh yes, to vacate space on your TM disk, go into Time Machine, right click the Parallels VM and select : delete all backups" or something similar there. It will remove all copies of that large file...

 

Honzall. Thank you fo that - what you say makes sense. I do have one question about your approach - if your VMs only contain the system and no data, how do you get them to access the data that you now keep on the Mac?

 

Do you realize, that you have number of options what to share between the host (Mac) and guest (Windows)?
In VM configuration - Options - Sharing - Shared profile you can get the two systems integrated more or less as tight as you want. I generally share only home folder, but you can integrate the two systems very tightly. It got really confusing for me when I shared desktops But it may be really useful if you need to run in Coherence, when the Windows programs look like they actually belong in Mac and the whole notion of Windows desktop does not really apply anymore
Anyway, you can make it work like the Documents folder from Mac is My Documents in Windows. Physically this will be on the Mac and therefore backuped by TM.

 

Honzall - thank you - I will exeriment