On 12/10/2013 03:33 PM, Alessandro MACUZ wrote: > 2013/12/10 Peter Rajnoha <prajnoha@redhat.com <mailto:prajnoha@redhat.com>> > > On 12/09/2013 04:13 PM, Umar Draz wrote: > > Hi All > > > > I have a SCSI share which i am using linux initiator on my > ubuntu. Its > > available for me in /dev/sdb > > > > No I have created lvm group using the /dev/sdb. Today I just logut and > > login my scsi share but this time ubutnu gave me this as /dev/sdc > > instead of /dev/sdb. > > > > due to this my lvm group is stuck, and its giving me the error > > > > Input/output error > > > > on pvdisplay or vgdisplay, > > > > Any body help me how I can reslove this issue.? > > > > You should always deactivate your LVM volumes before > disconnecting the underlying iSCSI volumes and then when > you reconnect the iSCSI back, activate the LVM volumes > (or if autoactivation is used - meaning use_lvmetad=1 > is set in lvm.conf, this activation happens automatically). > > Alternatively, you can call vgchange --refresh when the > iSCSI is connected back. > > > > Couldn't be used the identification of PV by UUID here? It should be > better imo. > Well, this is about dm tables that represent the logical volumes (you can check dmsetup table output). The PV UUID doesn't play a role at this level - the PV UUID is just LVM abstraction that is using device-mapper kernel capabilities. And if the iSCSI is disconnected while there's anything on top of it (in this case the LV), the major:minor pair (as well as the kernel name) is reserved until all the stack above it is freed. Then when the iSCSI is connected back (while the old major:minor is still held by old mapping), kernel has no other choice just to assign new major:minor pair. Therefore we need a refresh (or deactivation/activation) which will generate a new mapping with the new major:minor pair of the underlying PV (the iSCSI volume). -- Peter _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
