Hi, as far as I understand drbd9 is over lvm, and I have 2 SSD disks on each server, that I need to "sum" to have their total capacity. I will have an Adaptec 6805e raid controller.
The question is: is better create a raid0 with sdb+sdc at controller level, or create two separate raid0 disks (the controller does not let "single disks") and them use something like vgcreate drbdpool /dev/vdb1 /dev/vdc1 ?
What about trim support? I'm a lot confused about this issue, since I can enable Trim on the guest (fstab), as config flag when creating the VM, and also there is the "scsi-virtio" type of controller stuff that should "pass trims". Finally, drbd is over lvm that I don't know if is of with trims, and if the raid controller passes trim back to storage.
Final question, with DC class ssd (the new Samsung SM863 MZ-7KM960E, hoping to be able to set a better overprovisioning than default), is raid writeback controller cache (with bbu) necessary or not?
Thanks for the advices
The question is: is better create a raid0 with sdb+sdc at controller level, or create two separate raid0 disks (the controller does not let "single disks") and them use something like vgcreate drbdpool /dev/vdb1 /dev/vdc1 ?
What about trim support? I'm a lot confused about this issue, since I can enable Trim on the guest (fstab), as config flag when creating the VM, and also there is the "scsi-virtio" type of controller stuff that should "pass trims". Finally, drbd is over lvm that I don't know if is of with trims, and if the raid controller passes trim back to storage.
Final question, with DC class ssd (the new Samsung SM863 MZ-7KM960E, hoping to be able to set a better overprovisioning than default), is raid writeback controller cache (with bbu) necessary or not?
Thanks for the advices
