DRBD on LVM or LVM on DRBD with multiple disks

I have 4 identical servers each with 1+3 SSD for data (no RAID) + 2x10G & 2x1G net. I want to have an active-passive NFS setup with a single export. Probably I will go with 2 clusters so 2 active NFS servers/exports which will be mounted by many clients (as home dirs) with autofs so which server has the data is not important (having always a running cluster if one is down is a plus - upgrade/migration/failure); both will be backup-ed. I was thinking of going CEPH initially but:

• exporting with NFS and having an u/g/p quota I think it's impossible(?)
• going cephfs directly from clients complicates things (isolation, access control etc)
• plus replica 2 vs 3 = more capacity.

I still don't understand what's the relationship or how it's best and [dis]advantages:

1. 1xResource with 3x(Volumes < SSD) = 3x rdbd > 1xLV > XFS
2. 1xResource with 1x rdbd < 1LV < 3xSSD = rdbd > [?LV >] XFS [link]

I believe it's like with RAID 0+1 or 1+0 (with the diff. that is not striped) so option (1) is better to have individual disks replicated (multiple meta-disk) than a single volume replicated (single meta-disk probability to fail all), which in case of a disk failure is better ... I think? It's all about how a disk failure is handled right? Other suggestions or pov?

With 4 servers and all-SSD w/out any RAID your configuration simply begs for Ceph erasure-coded setup!

1. E/C pool creation (assuming you have Ceph cluster already)

https://subscription.packtpub.com/book/cloud-&-networking/9781784393502/8/ch08lvl1sec89/creating-an-erasure-coded-pool

2. NFS services on top of the freshly created in (1) E/C pool

https://access.redhat.com/documentation/en-us/red_hat_ceph_storage/5/html/dashboard_guide/management-of-nfs-ganesha-exports-on-the-ceph-dashboard

Do not use DRBD! It’s storage inefficient due to enormous replication overhead and “split brain” is DRBD’s second name…