DRBD 9 internal-metada vs makefs

Here are the steps I followed to create a two node DRBD 9 setup: 1. Create LVM 2. On each node created internal meta-data with drbdadm create-md 'resourcename' 3. On each node brought the resource up with drbdadm up 'resourcename' 4. Prompted one with drbdadm primary --force 'resourcename' as the primary node 5. Made it secondary again drbdadm secondary 'resourcename' 6. Formatted it makefs.ext4 /dev/drbd1 My question is, why does step 6 not wipe out the internal meta-data from step 2?