[Libguestfs] virt-sysprep future

[Richard W.M. Jones]

On Sat, Mar 17, 2012 at 06:59:34PM +0800, Wanlong Gao wrote:
> Does RedHat has a plan to support NBD in RHEL in the future?

Not as far as I know.

guestmount is fast enough for me.  With inspection:

$ time sh -c 'guestmount -a /dev/vg_pin/F16x64 -i /tmp/mnt; fusermount -u /tmp/mnt'

real   0m9.999s
user   0m0.081s
sys    0m0.377s

Without inspection:

$ time sh -c 'guestmount -a /dev/vg_pin/F16x64 -m /dev/vg_f16x64/lv_root /tmp/mnt; fusermount -u /tmp/mnt'

real   0m6.681s
user   0m0.074s
sys    0m0.339s

Currently virt-sysprep runs libguestfs twice (once for inspection,
once to mount).  A virt-sysprep that was rewritten not to be a shell
script would only run libguestfs once, so there would be ~10 second
overhead.  This overhead is insignificant compared to the downsides of
using nbd: having to run as root, (in)security, not supporting all
guests, creating host device nodes, etc.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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