We can use the same lvcreate utility that helped us provision the PostgreSQL volume. We start the command with the -l parameter set to 100%FREE to use any unallocated space in the VG_POSTGRES volume group. While we can specify sizes in MB or GB with the -L setting, we really only need to do this if we plan on creating multiple snapshots.
The -s parameter makes this volume a snapshot, which causes LVM to base its contents on those of another volume. Thus, we specify VG_POSTGRES/LV_DATA as the origin volume group and volume we want to use for the snapshot. We also use the -n parameter to set the name of the new volume to snap, making our intentions more obvious.
With the volume created, we simply need to mount it to access the ...