Red Hat Bugzilla – Bug 214908
Concurrent-access flag is not provided via libvirt's virDomainGetXMLDesc()
Last modified: 2007-11-30 17:07:37 EST
Config File: --------------------------------------------- # Automatically generated xen config file name = "kanderso-xen-22" memory = "1024" disk = [ 'phy:/dev/RootVolumes/Node2-02,xvda,w', 'phy:/dev/RootVolumes/ClusterFS0,xvdb,w!' ] # ^ xvdb is a shared disk image; note the ! flag. vif = [ 'mac=02:10:15:84:00:22, bridge=xenbr0', ] nographic=1 bootloader="/usr/bin/pygrub" vcpus=1 on_reboot = 'restart' on_crash = 'restart' ---------------------------------------------- Error Messages ---------------------------------------------- Rebooting domain kanderso-xen-22... [[ XML Domain Info ]] <domain type='xen' id='107'> <name>kanderso-xen-22</name> <uuid>0ac92eac79a37a1b541bd83d55ecb4c4</uuid> <bootloader>/usr/bin/pygrub</bootloader> <os> <type>linux</type> <kernel>/var/lib/xen/vmlinuz.Q8oxJB</kernel> <initrd>/var/lib/xen/initrd.ILqJte</initrd> <cmdline>ro root=/dev/VolGroup00/LogVol00 console=xvc0 rhgb quiet</cmdline> </os> <memory>1048576</memory> <vcpu>1</vcpu> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <devices> <interface type='bridge'> <source bridge='xenbr0'/> <mac address='02:10:15:84:00:22'/> <script path='vif-bridge'/> </interface> <disk type='block' device='disk'> <driver name='phy'/> <source dev='/dev/RootVolumes/Node2-02'/> <target dev='xvda'/> </disk> <disk type='block' device='disk'> <driver name='phy'/> <source dev='/dev/RootVolumes/ClusterFS0'/> <target dev='xvdb'/> </disk> <console tty='/dev/pts/5'/> </devices> </domain> [[ XML END ]] Clearing 212 bytes starting @ 0x6296d9 [[ XML Domain Info (modified) ]] <domain type='xen' id='107'> <name>kanderso-xen-22</name> <uuid>0ac92eac79a37a1b541bd83d55ecb4c4</uuid> <bootloader>/usr/bin/pygrub</bootloader> <memory>1048576</memory> <vcpu>1</vcpu> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <devices> <interface type='bridge'> <source bridge='xenbr0'/> <mac address='02:10:15:84:00:22'/> <script path='vif-bridge'/> </interface> <disk type='block' device='disk'> <driver name='phy'/> <source dev='/dev/RootVolumes/Node2-02'/> <target dev='xvda'/> </disk> <disk type='block' device='disk'> <driver name='phy'/> <source dev='/dev/RootVolumes/ClusterFS0'/> <target dev='xvdb'/> </disk> <console tty='/dev/pts/5'/> </devices> </domain> [[ XML END ]] Calling virDomainDestroy libvir: Xen Daemon error : GET operation failed: No such domain kanderso-xen-22 Domain no longer exists Calling virDomainCreateLinux()... libvir: Xen Daemon error : POST operation failed: (xend.err 'Device 51728 (vbd) could not be connected.\nDevice /dev/RootVolumes/ClusterFS0 is mounted in a guest domain,\nand so cannot be mounted now.') Failed to get devices for domain kanderso-xen-22 Expected results: Flag in XML description returned from virDomainGetXMLDesc() which indicates that the disk image is allowed to be used by more than one domain simultaneously (corresponding to the ! flag in the configuration). This should eliminate the error incurred. Additional info: 'xm create' always works correctly.
Created attachment 140848 [details] xm list --long of domain running w/ the w! flag.
Adding blocker flags for GA release. Not having this capability requires operator intervention after node failures in a cluster. This will block full verification and recovery testing in a virtual environment.
Ok, so we currently just check the (mode) bit of the sexpression for 'r' to signify read-only - assuming that the only other value was 'w' for writable. It appears we have an extra option to deal with: (mode 'w!') We need to check for that, and then probably add a '<sharable>' element in the disk specification, eg <disk type='block' device='disk'> <driver name='phy'/> <source dev='/dev/RootVolumes/ClusterFS0'/> <target dev='xvdb'/> <sharable/> </disk>
Easy enough, I have an early patch, attached, not yet commited I need to add regression tests first, getting it upstream is no brainer, getting it in RHEL5 is another piece of cake ! Daniel
Created attachment 140884 [details] patch to support shrareable disks
patch has been commited in libvirt upstream, Daniel
QE ack for RHEL5 . . . comment 2 pretty well sums things up.
libvirt-0.1.8-3.el5 has been built with the fix to test, Daniel
A package has been built which should help the problem described in this bug report. This report is therefore being closed with a resolution of CURRENTRELEASE. You may reopen this bug report if the solution does not work for you.