Attempting to extend a RHEV Storage Domain fails with "Failed to connect Host <UNKNOWN> to device."

Solution Verified - Updated -


  • LUN addition fails with the following error reported in the Events pane in the RHEV-M GUI;
Failed to connect Host <UNKNOWN> to device.
  • All the virtual machines on the hypervisor became unresponsive, although the hypervisor itself stayed Up. None of the VM's could be reset, powered off, shutdown, etc.

  • An attempt to extend a Storage Domain failed with an ERROR_CANNOT_EXTEND_CONNECTION_FAILED error reported in the var/log/ovirt-engine/engine.log file;

2013-07-05 00:00:51,510 ERROR [] (http-/ [422c5cb6] Transaction rolled-back for command:
2013-07-05 00:00:51,540 WARN  [] (http-/ [422c5cb6] CanDoAction of action ExtendSANStorageDomain failed. Reasons:VAR__TYPE__STORAGE__DOMAIN,VAR__ACTION__EXTEND,ERROR_CANNOT_EXTEND_CONNECTION_FAILED,$lun  


  • Red Hat Enterprise Virtualization (RHEV) 3.1
  • Red Hat Enterprise Linux (RHEL) 6.4 hosts
    • vdsm-4.10.2-1.13
    • libvirt-0.10.2-18.el6_4.5

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