We are updating some machines in our server farm to Ubuntu natty (KVM / Opennebula cluster). Since then we used to have some VM with shared read-only IDE disks to mirror software repositories through several isolated networks (one-way data diode).
The updated qemu does not allow it. It failed to start the VM with a 'Can't use a read-only drive' error. After checking in the qemu git, it seems that this has been forbidden by this commit '7aa9c811ca0761918a0252d0f923a80224953fa6' :
----------------------------- Author: Markus Armbruster <address@hidden> 2010-06-28 19:10:36 Committer: Kevin Wolf <address@hidden> 2010-07-06 17:05:50
Parent: c4d74df726cb3791d9f1661b58067df5608b627e (ide: Make ide_init_drive() return success) Child: dce9e92834cc4f962e547cae46b73ca559d05b0c (ide: Reject invalid CHS geometry) Branches: master, remotes/origin/master, remotes/origin/stable-0.13, remotes/origin/stable-0.14, remotes/origin/stable-0.15
Follows: v0.12.0-rc0 Precedes: v0.13.0-rc0
ide: Reject readonly drives unless CD-ROM
drive_init() doesn't permit option readonly for if=ide, but that's worthless: we get it via if=none and -device.
Signed-off-by: Markus Armbruster <address@hidden> Signed-off-by: Kevin Wolf <address@hidden> -----------------------------
I do not understand the comment, if there is a workaround or if it something to avoid.