On Thursday 04 May 2006 16:14, Nic wrote: > Is it possible to mount a cow file and it's backing fs as a loop back > filesystem on the host? > > ie: shut down your VM and mount the VMs filesystem on the host in > order to write something into it?
No, there's no way to mount COW files on host. Use plain UBD files if you need that,or access them from UML itself (this doesn't work in a recovery situation, however). However, there's a (hard) way: you can use device-mapper (dmsetup command) to do the same job - you can create a COW volume on the host with two block devices* (via the snapshot target, see Documentation/device-mapper/snapshot.txt in a 2.6.15+ linux kernel tree) and pass it to UML as ubd0=/dev/mapper/volume after giving write access on the device. It's not easy to do however, I wanted to write an interface for this but didn't finish it. In particular, you can create the volume with two LVM devices, but the creation of a COW volume cannot be done with LVM,it does not provide this ability. * two partitions or more likely two LVM volumes. -- Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!". Paolo Giarrusso, aka Blaisorblade (Skype ID "PaoloGiarrusso", ICQ 215621894) http://www.user-mode-linux.org/~blaisorblade Chiacchiera con i tuoi amici in tempo reale! http://it.yahoo.com/mail_it/foot/*http://it.messenger.yahoo.com ------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ User-mode-linux-user mailing list User-mode-linux-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user
