The reason: the implementation of lvremove / dev / system / lv_trans delete logical partition
restore:
1, into the lvm view metadata
cd /etc/lvm/archive
2, the restoring metadata volume group vg
vgcfgrestore system_0000 (metadata file)
3, the activation volume group vg
vgchange -ay /dev/system/lv_trans
4, remount
mount /dev/system/lv_trants /usr/sap/trans