Hello Amit. Thanks for you reply. This is the content of /etc/sudoers.d/50_vdsm file (it's the default generated by ovirt install): Cmnd_Alias VDSM_LIFECYCLE = \ /usr/sbin/dmidecode -s system-uuid Cmnd_Alias VDSM_STORAGE = \ /usr/sbin/fsck -p *, \ /usr/sbin/tune2fs -j *, \ /usr/sbin/mkfs -q -j *, \ /usr/bin/kill, \ /usr/bin/chown vdsm\:qemu *, \ /usr/bin/chown vdsm\:kvm *, \ /usr/sbin/iscsiadm *, \ /usr/sbin/lvm, \ /usr/bin/setsid /usr/bin/ionice -c ? -n ? /usr/bin/su vdsm -s /bin/sh -c /usr/libexec/vdsm/spmprotect.sh*, \ /usr/sbin/service vdsmd *, \ /usr/sbin/reboot -f vdsm ALL=(ALL) NOPASSWD: VDSM_LIFECYCLE, VDSM_STORAGE Defaults:vdsm !requiretty Defaults:vdsm !syslog I was pretty curious about the format of the line "/usr/bin/setsid /usr/bin/ionice -c ? -n ? /usr/bin/su vdsm -s /bin/sh -c /usr/libexec/vdsm/spmprotect.sh*", but looking at source code (https://github.com/oVirt/vdsm/blob/master/static/etc/sudoers.d/50_vdsm.in) it looks to be just like that. If I need to change anything on this file, it looks that there's some bug on vdsm package. In other hand, I watched the /var/log/secure file while I was trying to attach a Datacenter to ISO Domain and it didn't showed anything new, meaning that the referred "ionice" command was not executed via sudo by vdsm. If it's is true, that could explain the "permission denied" error. About the NFS export, it is exactly the same as parameters as Data Domain exports (which works perfectly): exportfs -v /storage/vm 172.31.17.0/24(sync,wdelay,hide,no_subtree_check,sec=sys,rw,secure,root_squash,no_all_squash) /storage/vm 172.31.48.0/24(sync,wdelay,hide,no_subtree_check,sec=sys,rw,secure,root_squash,no_all_squash) /storage/iso <world>(sync,wdelay,hide,no_subtree_check,sec=sys,rw,secure,root_squash,no_all_squash) What else do I need to check? Thanks Ivan