How to use qcow2 disk image in Linux?

Posted by sauparna on Super User See other posts from Super User or by sauparna
Published on 2010-12-27T09:02:33Z Indexed on 2010/12/27 9:55 UTC
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linux

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mount

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disk

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qemu

I have a large qcow2 formatted disk image, which I use as storage. Often I need to move data to and from this disk image. I mount the disk using the qemu-nbd tool as follows:

modprobe nbd max_part=63
qemu-nbd -c /dev/nbd0 /host/disk100G.img
mount /dev/nbd0p1 /home/rup/disk

But disk access fails every now and then in the midst of some I/O operation with an "Input/output error". At that point I have to manually unmount the disk and re-mount it so that I can run the program again:

qemu-nbd -d /dev/nbd0
umount joborkhaki/

What could be the reason for this? Is there a better tool that I can use to maintain a qcow2 disk image?

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