HP Z420 passthru of SATA drives

[rcd]

I have a HP Z420 with 8 SATA drive connectors. According to the documentation it is 2 x 2 AHCI and 1 x 4 SCU, see diagram below.

Currently I have a system drive on (15), 4 of 5 raidz drives on (17) and the last raidz drive on (14).

I'd like to passthru the raidz drives to a VM, so I'm trying to find out which device ID's correspond to these connectors.

# lspci | grep SATA
00:1f.2 IDE interface: Intel Corporation C600/X79 series chipset 4-Port SATA IDE Controller (rev 05)
00:1f.5 IDE interface: Intel Corporation C600/X79 series chipset 2-Port SATA IDE Controller (rev 05)
02:00.0 Serial Attached SCSI controller: Intel Corporation C602 chipset 4-Port SATA Storage Control Unit (rev 05)

Q1: So I'd pass the 02:00.0 to the VM for 4 of the raidz drives, but what about the last drive? Will I be able to pass it without passing the system drive? Like I explained above, the system drive and the last raidz drive are physically connected to different areas of the MB, that seems to be separate controllers, but how do I know?

Q2: Alternatively I could buy an M.2 PCIe adaptor with a NVME SSD drive like a Samsung 980 for system drive. My MB don't have onboard M.2 adaptor but I have a free PCIe slot for it and it would clean up a bit of wiring mess. On the other hand I don't know if this solution would be compatible with Proxmox? I read some people had problems getting it to recognize NVME drives for booting.

 

[Dunuin]

# lspci | grep SATA
00:1f.2 IDE interface: Intel Corporation C600/X79 series chipset 4-Port SATA IDE Controller (rev 05)
00:1f.5 IDE interface: Intel Corporation C600/X79 series chipset 2-Port SATA IDE Controller (rev 05)
02:00.0 Serial Attached SCSI controller: Intel Corporation C602 chipset 4-Port SATA Storage Control Unit (rev 05)

Q1: So I'd pass the 02:00.0 to the VM for 4 of the raidz drives, but what about the last drive? Will I be able to pass it without passing the system drive? Like I explained above, the system drive and the last raidz drive are physically connected to different areas of the MB, that seems to be separate controllers, but how do I know?

All 6 ports are the same controller of your mainboards chipset. But as long as both function of that controller got their own IOMMU group that could still work. Did you follow the PCI passthrough guide and checked with find /sys/kernel/iommu_groups/ -type l if they got dedicated IOMMU goups?

Q2: Alternatively I could buy an M.2 PCIe adaptor with a NVME SSD drive like a Samsung 980 for system drive. My MB don't have onboard M.2 adaptor but I have a free PCIe slot for it and it would clean up a bit of wiring mess. On the other hand I don't know if this solution would be compatible with Proxmox? I read some people had problems getting it to recognize NVME drives for booting.

That depends. If your board doesn't got a M.2 slot I wouldn't wonder if the UEFI wouldn't be able to boot from an NVMe. Then a NVMe would be fine as a data drive but not for your PVE OS. You could ask the HP support if your motherboards UEFI supports that.

Maybe @avw knows this for your chipset.

 

[rcd]

All 6 ports are the same controller of your mainboards chipset. But as long as both function of that controller got their own IOMMU group that could still work. Did you follow the PCI passthrough guide and checked with find /sys/kernel/iommu_groups/ -type l if they got dedicated IOMMU goups?

Yes, I think they are all there:

# find /sys/kernel/iommu_groups/ -type l | grep "02:00\|00:1f"
/sys/kernel/iommu_groups/25/devices/0000:00:1f.2
/sys/kernel/iommu_groups/25/devices/0000:00:1f.0
/sys/kernel/iommu_groups/25/devices/0000:00:1f.5
/sys/kernel/iommu_groups/25/devices/0000:00:1f.3
/sys/kernel/iommu_groups/27/devices/0000:02:00.0

Unfortunately I think it'd be hard to find anyone still working with HP who know about this server. it's got more than a few years on it's back

 

[Dunuin]

Both of the chipset SATA controller functions use the same IOMMU group. You could try to force breaking down IOMMU groups using ACS override but that can cause alot of troubles.

So doesn't look good.
Some people boot from USB/SD card but then use a NVMe as the actual PVE system disk. Thats a workaround you could try if booting from NVMe isn't supported.

What devices are 0000:00:1f.0 and 0000:00:1f.3?

 

[rcd]

Both of the chipset SATA controller functions use the same IOMMU group. You could try to force breaking down IOMMU groups using ACS override but that can cause alot of troubles.

So doesn't look good.
Some people boot from USB/SD card but then use a NVMe as the actual PVE system disk. Thats a workaround you could try if booting from NVMe isn't supported.

What devices are 0000:00:1f.0 and 0000:00:1f.3?

I don't know. How can I find out?

Booting from a USB stick could be a possibility, though I had a quick google and it does seem a bit fiddly. Maybe just buy a 5 port PCIe adaptor, amazon have a couple different models from around €50 - would something like this work with Proxmox?

 

[Neobin]

Please post the full output from the PVE-host in code-tags of:

for d in /sys/kernel/iommu_groups/*/devices/*; do n=${d#*/iommu_groups/*}; n=${n%%/*}; printf 'IOMMU group %s ' "$n"; lspci -nns "${d##*/}"; done

(Thanks to @avw for the command!)

 

[rcd]

# for d in /sys/kernel/iommu_groups/*/devices/*; do n=${d#*/iommu_groups/*}; n=${n%%/*}; printf 'IOMMU group %s ' "$n"; lspci -nns "${d##*/}"; done
IOMMU group 0 00:00.0 Host bridge [0600]: Intel Corporation Xeon E5/Core i7 DMI2 [8086:3c00] (rev 07)
IOMMU group 10 00:04.6 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DMA Channel 6 [8086:3c26] (rev 07)
IOMMU group 11 00:04.7 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DMA Channel 7 [8086:3c27] (rev 07)
IOMMU group 12 00:05.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Address Map, VTd_Misc, System Management [8086:3c28] (rev 07)
IOMMU group 13 00:05.2 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Control Status and Global Errors [8086:3c2a] (rev 07)
IOMMU group 14 00:05.4 PIC [0800]: Intel Corporation Xeon E5/Core i7 I/O APIC [8086:3c2c] (rev 07)
IOMMU group 15 00:11.0 PCI bridge [0604]: Intel Corporation C600/X79 series chipset PCI Express Virtual Root Port [8086:1d3e] (rev 05)
IOMMU group 16 00:19.0 Ethernet controller [0200]: Intel Corporation 82579LM Gigabit Network Connection (Lewisville) [8086:1502] (rev 05)
IOMMU group 17 00:1a.0 USB controller [0c03]: Intel Corporation C600/X79 series chipset USB2 Enhanced Host Controller #2 [8086:1d2d] (rev 05)
IOMMU group 18 00:1b.0 Audio device [0403]: Intel Corporation C600/X79 series chipset High Definition Audio Controller [8086:1d20] (rev 05)
IOMMU group 19 00:1c.0 PCI bridge [0604]: Intel Corporation C600/X79 series chipset PCI Express Root Port 2 [8086:1d12] (rev b5)
IOMMU group 1 00:01.0 PCI bridge [0604]: Intel Corporation Xeon E5/Core i7 IIO PCI Express Root Port 1a [8086:3c02] (rev 07)
IOMMU group 20 00:1c.5 PCI bridge [0604]: Intel Corporation C600/X79 series chipset PCI Express Root Port 5 [8086:1d18] (rev b5)
IOMMU group 21 00:1c.6 PCI bridge [0604]: Intel Corporation C600/X79 series chipset PCI Express Root Port 3 [8086:1d14] (rev b5)
IOMMU group 22 00:1c.7 PCI bridge [0604]: Intel Corporation C600/X79 series chipset PCI Express Root Port 4 [8086:1d16] (rev b5)
IOMMU group 23 00:1d.0 USB controller [0c03]: Intel Corporation C600/X79 series chipset USB2 Enhanced Host Controller #1 [8086:1d26] (rev 05)
IOMMU group 24 00:1e.0 PCI bridge [0604]: Intel Corporation 82801 PCI Bridge [8086:244e] (rev a5)
IOMMU group 24 09:05.0 FireWire (IEEE 1394) [0c00]: LSI Corporation FW322/323 [TrueFire] 1394a Controller [11c1:5811] (rev 70)
IOMMU group 25 00:1f.0 ISA bridge [0601]: Intel Corporation C600/X79 series chipset LPC Controller [8086:1d41] (rev 05)
IOMMU group 25 00:1f.2 IDE interface [0101]: Intel Corporation C600/X79 series chipset 4-Port SATA IDE Controller [8086:1d00] (rev 05)
IOMMU group 25 00:1f.3 SMBus [0c05]: Intel Corporation C600/X79 series chipset SMBus Host Controller [8086:1d22] (rev 05)
IOMMU group 25 00:1f.5 IDE interface [0101]: Intel Corporation C600/X79 series chipset 2-Port SATA IDE Controller [8086:1d08] (rev 05)
IOMMU group 26 05:00.0 VGA compatible controller [0300]: NVIDIA Corporation GF119 [NVS 310] [10de:107d] (rev a1)
IOMMU group 26 05:00.1 Audio device [0403]: NVIDIA Corporation GF119 HDMI Audio Controller [10de:0e08] (rev a1)
IOMMU group 27 02:00.0 Serial Attached SCSI controller [0107]: Intel Corporation C602 chipset 4-Port SATA Storage Control Unit [8086:1d6b] (rev 05)
IOMMU group 28 07:00.0 Ethernet controller [0200]: Broadcom Inc. and subsidiaries NetXtreme II BCM5709 Gigabit Ethernet [14e4:1639] (rev 20)
IOMMU group 28 07:00.1 Ethernet controller [0200]: Broadcom Inc. and subsidiaries NetXtreme II BCM5709 Gigabit Ethernet [14e4:1639] (rev 20)
IOMMU group 29 08:00.0 USB controller [0c03]: Texas Instruments TUSB73x0 SuperSpeed USB 3.0 xHCI Host Controller [104c:8241] (rev 02)
IOMMU group 2 00:02.0 PCI bridge [0604]: Intel Corporation Xeon E5/Core i7 IIO PCI Express Root Port 2a [8086:3c04] (rev 07)
IOMMU group 30 7f:08.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 QPI Link 0 [8086:3c80] (rev 07)
IOMMU group 31 7f:08.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 QPI Link Reut 0 [8086:3c83] (rev 07)
IOMMU group 32 7f:08.4 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 QPI Link Reut 0 [8086:3c84] (rev 07)
IOMMU group 33 7f:09.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 QPI Link 1 [8086:3c90] (rev 07)
IOMMU group 34 7f:09.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 QPI Link Reut 1 [8086:3c93] (rev 07)
IOMMU group 35 7f:09.4 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 QPI Link Reut 1 [8086:3c94] (rev 07)
IOMMU group 36 7f:0a.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Power Control Unit 0 [8086:3cc0] (rev 07)
IOMMU group 36 7f:0a.1 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Power Control Unit 1 [8086:3cc1] (rev 07)
IOMMU group 36 7f:0a.2 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Power Control Unit 2 [8086:3cc2] (rev 07)
IOMMU group 36 7f:0a.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Power Control Unit 3 [8086:3cd0] (rev 07)
IOMMU group 37 7f:0b.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Interrupt Control Registers [8086:3ce0] (rev 07)
IOMMU group 37 7f:0b.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Semaphore and Scratchpad Configuration Registers [8086:3ce3] (rev 07)
IOMMU group 38 7f:0c.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Unicast Register 0 [8086:3ce8] (rev 07)
IOMMU group 38 7f:0c.1 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Unicast Register 0 [8086:3ce8] (rev 07)
IOMMU group 38 7f:0c.2 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Unicast Register 0 [8086:3ce8] (rev 07)
IOMMU group 38 7f:0c.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Unicast Register 0 [8086:3ce8] (rev 07)
IOMMU group 38 7f:0c.6 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller System Address Decoder 0 [8086:3cf4] (rev 07)
IOMMU group 38 7f:0c.7 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 System Address Decoder [8086:3cf6] (rev 07)
IOMMU group 39 7f:0d.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Unicast Register 0 [8086:3ce8] (rev 07)
IOMMU group 39 7f:0d.1 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Unicast Register 0 [8086:3ce8] (rev 07)
IOMMU group 39 7f:0d.2 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Unicast Register 0 [8086:3ce8] (rev 07)
IOMMU group 39 7f:0d.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Unicast Register 0 [8086:3ce8] (rev 07)
IOMMU group 39 7f:0d.6 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller System Address Decoder 1 [8086:3cf5] (rev 07)
IOMMU group 3 00:03.0 PCI bridge [0604]: Intel Corporation Xeon E5/Core i7 IIO PCI Express Root Port 3a in PCI Express Mode [8086:3c08] (rev 07)
IOMMU group 40 7f:0e.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Processor Home Agent [8086:3ca0] (rev 07)
IOMMU group 40 7f:0e.1 Performance counters [1101]: Intel Corporation Xeon E5/Core i7 Processor Home Agent Performance Monitoring [8086:3c46] (rev 07)
IOMMU group 41 7f:0f.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Registers [8086:3ca8] (rev 07)
IOMMU group 42 7f:0f.1 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller RAS Registers [8086:3c71] (rev 07)
IOMMU group 43 7f:0f.2 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Target Address Decoder 0 [8086:3caa] (rev 07)
IOMMU group 44 7f:0f.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Target Address Decoder 1 [8086:3cab] (rev 07)
IOMMU group 45 7f:0f.4 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Target Address Decoder 2 [8086:3cac] (rev 07)
IOMMU group 46 7f:0f.5 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Target Address Decoder 3 [8086:3cad] (rev 07)
IOMMU group 47 7f:0f.6 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Target Address Decoder 4 [8086:3cae] (rev 07)
IOMMU group 48 7f:10.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Channel 0-3 Thermal Control 0 [8086:3cb0] (rev 07)
IOMMU group 49 7f:10.1 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Channel 0-3 Thermal Control 1 [8086:3cb1] (rev 07)
IOMMU group 4 00:04.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DMA Channel 0 [8086:3c20] (rev 07)
IOMMU group 50 7f:10.2 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller ERROR Registers 0 [8086:3cb2] (rev 07)
IOMMU group 51 7f:10.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller ERROR Registers 1 [8086:3cb3] (rev 07)
IOMMU group 52 7f:10.4 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Channel 0-3 Thermal Control 2 [8086:3cb4] (rev 07)
IOMMU group 53 7f:10.5 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller Channel 0-3 Thermal Control 3 [8086:3cb5] (rev 07)
IOMMU group 54 7f:10.6 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller ERROR Registers 2 [8086:3cb6] (rev 07)
IOMMU group 55 7f:10.7 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Integrated Memory Controller ERROR Registers 3 [8086:3cb7] (rev 07)
IOMMU group 56 7f:11.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DDRIO [8086:3cb8] (rev 07)
IOMMU group 57 7f:13.0 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 R2PCIe [8086:3ce4] (rev 07)
IOMMU group 57 7f:13.1 Performance counters [1101]: Intel Corporation Xeon E5/Core i7 Ring to PCI Express Performance Monitor [8086:3c43] (rev 07)
IOMMU group 57 7f:13.4 Performance counters [1101]: Intel Corporation Xeon E5/Core i7 QuickPath Interconnect Agent Ring Registers [8086:3ce6] (rev 07)
IOMMU group 57 7f:13.5 Performance counters [1101]: Intel Corporation Xeon E5/Core i7 Ring to QuickPath Interconnect Link 0 Performance Monitor [8086:3c44] (rev 07)
IOMMU group 57 7f:13.6 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 Ring to QuickPath Interconnect Link 1 Performance Monitor [8086:3c45] (rev 07)
IOMMU group 5 00:04.1 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DMA Channel 1 [8086:3c21] (rev 07)
IOMMU group 6 00:04.2 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DMA Channel 2 [8086:3c22] (rev 07)
IOMMU group 7 00:04.3 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DMA Channel 3 [8086:3c23] (rev 07)
IOMMU group 8 00:04.4 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DMA Channel 4 [8086:3c24] (rev 07)
IOMMU group 9 00:04.5 System peripheral [0880]: Intel Corporation Xeon E5/Core i7 DMA Channel 5 [8086:3c25] (rev 07)
#

 

[leesteken]

I took the liberty to clean up the groups (removing bridges and devices you'll probably won't/can't passthrough):
IOMMU group 16 00:19.0 Ethernet controller [0200]: Intel Corporation 82579LM Gigabit Network Connection (Lewisville) [8086:1502] (rev 05) IOMMU group 17 00:1a.0 USB controller [0c03]: Intel Corporation C600/X79 series chipset USB2 Enhanced Host Controller #2 [8086:1d2d] (rev 05) IOMMU group 18 00:1b.0 Audio device [0403]: Intel Corporation C600/X79 series chipset High Definition Audio Controller [8086:1d20] (rev 05) IOMMU group 23 00:1d.0 USB controller [0c03]: Intel Corporation C600/X79 series chipset USB2 Enhanced Host Controller #1 [8086:1d26] (rev 05) IOMMU group 24 09:05.0 FireWire (IEEE 1394) [0c00]: LSI Corporation FW322/323 [TrueFire] 1394a Controller [11c1:5811] (rev 70) IOMMU group 25 00:1f.2 IDE interface [0101]: Intel Corporation C600/X79 series chipset 4-Port SATA IDE Controller [8086:1d00] (rev 05) IOMMU group 25 00:1f.3 SMBus [0c05]: Intel Corporation C600/X79 series chipset SMBus Host Controller [8086:1d22] (rev 05) IOMMU group 25 00:1f.5 IDE interface [0101]: Intel Corporation C600/X79 series chipset 2-Port SATA IDE Controller [8086:1d08] (rev 05) IOMMU group 26 05:00.0 VGA compatible controller [0300]: NVIDIA Corporation GF119 [NVS 310] [10de:107d] (rev a1) IOMMU group 26 05:00.1 Audio device [0403]: NVIDIA Corporation GF119 HDMI Audio Controller [10de:0e08] (rev a1) IOMMU group 27 02:00.0 Serial Attached SCSI controller [0107]: Intel Corporation C602 chipset 4-Port SATA Storage Control Unit [8086:1d6b] (rev 05) IOMMU group 28 07:00.0 Ethernet controller [0200]: Broadcom Inc. and subsidiaries NetXtreme II BCM5709 Gigabit Ethernet [14e4:1639] (rev 20) IOMMU group 28 07:00.1 Ethernet controller [0200]: Broadcom Inc. and subsidiaries NetXtreme II BCM5709 Gigabit Ethernet [14e4:1639] (rev 20) IOMMU group 29 08:00.0 USB controller [0c03]: Texas Instruments TUSB73x0 SuperSpeed USB 3.0 xHCI Host Controller [104c:8241] (rev 02)

Looks like the SAS controller is alone in group 27 and you might be able to pass it through. I believe you can connect SATA drives to certain SAS controller with the right cables (or maybe it does have 4 SATA ports). I looks like your motherboard has 10 SATA ports in total.
You could try passthrough of 00:1f.2 and 00:1f.5, which will give the whole group 25 to the VM with 6 SATA ports. Or just passthrough the disks instead of PCI passthrough.

 

[rcd]

Looks like the SAS controller is alone in group 27 and you might be able to pass it through. I believe you can connect SATA drives to certain SAS controller with the right cables (or maybe it does have 4 SATA ports). I looks like your motherboard has 10 SATA ports in total.
You could try passthrough of 00:1f.2 and 00:1f.5, which will give the whole group 25 to the VM with 6 SATA ports. Or just passthrough the disks instead of PCI passthrough.

Yes that is correct, like I was explaining in my OP 4 of the 5 raidz drives re connected to this SAS/SATA controller and probably can be passed through without problem. The problem is the last drive that seems to share controller with the system drive.

What would be the implication of just passing through the drives? I expect the VM will not be able to run things like smartctl, anything else? I guess that could be done on the host anyway if needed?

I guess if one drive needs to be passed through it's best to do it with all drives and not have a mix of drives and controllers passed through to the VM?

Other than that, any performance penalty?

Edit - the MB may have 10 logical SATA ports but only 8 physical.

 

[leesteken]

I was suggesting trying to use the 6 ports for your raidz, because it might fine to passthrough group 25. However, I just now start to understand that that group only has 4 physical ports? If you cannot passthrough both groups of 4, then you're stuck with 5+ drives.
I guess that leaves no other option: just use disk passthrough, which does make the disks show up as QEMU drives without serial numbers and also SMART won't work, but I believe that the overhead is small. In my experience ZFS's check-summing works better than SMART anyway.
You could combine both ways, but I don't see what benefits that would give you. Also, with PCI passthrough memory ballooning can't work, which means that the VM cannot shrink its cache memory to benefit other VMs.

 

[rcd]

Yes, there are only 8 physical ports on the MB - 4 for group 25 and 4 for group 27 - so I guess I'll have to pass through the individual drives or buy a new 5 port controller.
How do you pass through individual drives anyway, I don't see any way to do it through the GUI?

 

[leesteken]

How do you pass through individual drives anyway, I don't see any way to do it through the GUI?

Please have a look at the Proxmox wiki I've been linking to (the orange clickable part). It has examples like qm set 592 -scsi2 /dev/disk/by-id/ata-ST3000DM001-1CH166_Z1F41BLC, which can only be used on the Proxmox console or command line. I don't think there is a way to do it with the Proxmox web GUI,

 

[rcd]

Ok, thanks!
So just passing through drives and not using PCI then has the implicit advantage of not affecting memory balooning?

 

[Dunuin]

Jup. Using any PCI pasthrough always prevents memory ballooning for that VM.

 

[leesteken]

So just passing through drives and not using PCI then has the implicit advantage of not affecting memory balooning?

Most PCI(e) devices can do Direct Memory Access (DMA) and read/write any part of the VM memory at any time. For isolation/security, that memory cannot be (temporarily) given to another VM or back to the host and must be pinned into actual RAM at all times.