3nodes Ceph with 2xSSD in Raid1 for Proxmox + Journal, 24x1.2TB for OSD

[Icefire]

Pretty new to Ceph and even Proxmox.
I'm currently getting my 3rd server identical as my 2 others (2x28core+HT, 512gb ram) with 2 SSD + 24 1.2Tb SAS drive.

How would you configure that? I'm running a few VM, mostly not data intensive (got 4 Tb of enterprise data currently)
I want the servers to be clusterd/HA and plan for SSD/HD/server failure.

Would making a software Raid1 on the SSD for Proxmox than using the rest as Journal for Ceph a good idea?
a quick read was that Raid 1 for journal not good and loosing a disk when you loose have the journals a catastrophic failure..

having 3 nodes make it 6 SSD for journals. Do they rebuild if 1 fail?

 

[gurubert]

12 HDD OSDs on one SSD (how large are they?) is a bit too much as failure domain and IOPS stress on the SSD.
And you should not use these SSDs for the Proxmox installation if they are to be used as RocksDB partitions (there is no journal any more for Ceph OSDs). HDD-OSDs always need their RocksDB and WAL on SSD, otherwise the performance will be unusable.