vgexport and vgimport commands when you do this.
vgexport command makes an inactive volume group inaccessible to the system, which allows you to detach its physical volumes. The vgimport command makes a volume group accessible to a machine again after the vgexport command has made it inactive.
-a n argument of the vgchange command to mark the volume group as inactive, which prevents any further activity on the volume group.
vgexport command to export the volume group. This prevents it from being accessed by the system from which you are removing it.
pvscan command, as in the following example.
[root@tng3-1]# pvscan
PV /dev/sda1 is in exported VG myvg [17.15 GB / 7.15 GB free]
PV /dev/sdc1 is in exported VG myvg [17.15 GB / 15.15 GB free]
PV /dev/sdd1 is in exported VG myvg [17.15 GB / 15.15 GB free]
...
vgimport command to import the volume group, making it accessible to the new system.
-a y argument of the vgchange command.