So earlier today, I had a need to mount a disk image from a virtual machine on the host, and discovered a “new” method before remembering I’d made notes on this in the past. So I’m recording the details in the probably vain hope that I’ll remember this post in the future.
The first thing to do is to add an option to include partition support in the relevant kernel module, which I’ve done by adding a line to /etc/modprobe.d/etc-modules-parameters.conf :-
options nbd max_part=63
The next step is to load the module:
# modprobe nbd
The next is to use a Qemu tool to connect a disk image to a network block device :-
# qemu-nbd -r -c /dev/nbd0 /home/mike/lib/virtual-machine-disks/W10.vdi # ls /dev/nbd0* /dev/nbd0 /dev/nbd0p1 /dev/nbd0p2 /dev/nbd0p3
And next mount the relevant partition :-
# mount -o ro /dev/nbd0p2 /mnt
All done! Except for un-mounting it and finally disconnecting the network block device :-
# umount /mnt # ls /dev/nbd0* /dev/nbd0 /dev/nbd0p1 /dev/nbd0p2 /dev/nbd0p3 # qemu-nbd -d /dev/nbd0 /dev/nbd0 disconnected # ls /dev/nbd0* /dev/nbd0
The trickiest part is the qemu-nbd command (so not very tricky at all).
The “-r” option specifies that the disk image should be connected read-only, which seems to be sensible when you’re working with a disk image that “belongs” to another machine. Obviously if you need to write to the disk image then you should drop the “-r” (but consider cloning or taking a snapshot).
The “-c” option connects the disk image to a specific device and the “-d” option disconnects the specific device.
Just a test really … and a demonstration of why you need to print big (one of those black blobs on the water is a guy on a board).
(This is definitely a work in progress; I’ve still got more lens adaptors to buy and more lenses to test)
So I have a new Fujifilm GFX50R with one native lens (63mm) and my fortunes don’t extend to buying more lenses any time soon. Yet I hear that some 35mm lenses will work even though they’re designed to cover the smaller sensor of 35mm (or in many of the cases below 35mm film).
As someone who has been sticking third-party lenses (and I don’t mean Sigma lenses with an EF mount) on my Canon cameras for years the obvious thing to do is buy some adaptors to test the lenses I have.
And on the grounds that I would find this information useful if someone else had posted it (and I’d found it), I decided to put this out there. No guarantees on the accuracy though!
- No, the images aren’t meant to look good; most of this testing was done inside after a long day staring at a computer screen. The subject is boring, the focus may be off, and if you think these images represent what I’m capable of I’ll just roll about the floor laughing (and I’m not that good). When of course I add the images to this posting.
- If you have to have a “smart” lens adaptor for Canon EF lenses, choose a good one. The first one I bought was rubbish; I’ve since gone with a Kipon branded one.
- The column for “soft vignetting’ is particularly dubious; I’m not great at spotting it in the first place and until I move the images onto a computer screen and take a closer look I wouldn’t guarantee anything.
|Lens||Photo?||Soft Vignetting||Hard Vignetting||Sample (links)|
|Zeiss Makro-Planar 2/100mm ZE||✓||No||No||1|
|Zeiss Distagon 21/2.8 ZE||✓||No||Yes||1|
|MC Zenitar 16/2.8||✗||–||Yes|
|Sigma 12-24 @ 12mm||✓||No||No|
|Sigma 12-24 @ 24mm||✓||Yes||Yes|
|Canon 24-105mm f/4.0 L||✗||Yes||Yes|
|Canon 200-400mm mk1 @ 200||✗||No||No|
|Canon 200-400mm mk1 @ 400||✗||–||Yes|
|Leica Elmarit-R 2.8/19mm (1977)||✗||–||Yes|
|Leica Summilux-R 1.4/50mm (1971)||✗||Below f/11||No|
|Leica Elmarit-R 2.8/35mm (1984)||✗||Yes||No|
|Leica Elmarit-R 2.8/180mm (1975)||✓||No||No|
|Leica Elmarit-R 2.8/90mm (1966)||✓||No||No||1|
|Leica Macro-Elmerit-R 2.8/60mm (1977)||✓||Below f/4.0||No|
|Leica Summicron-R 2/50mm (1965)||TODO||TODO||TODO|
|Olympus OM 18mm f/3.5||✓||–||Yes|
|Olympus OM 85mm f/2.0||✓||Yes||No|
|Olympus OM 35mm f/2.8||✓||Yes||No|
|Carl Zeiss Jena 3.5/135mm||✓||No||No||1|