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new f9c44209 Add recommendations on UEFI instances controllers (#655)
f9c44209 is described below
commit f9c442095960751bd073a58982ce85d91d95dd38
Author: Harikrishna <[email protected]>
AuthorDate: Mon May 25 17:28:28 2026 +0530
Add recommendations on UEFI instances controllers (#655)
---
source/adminguide/virtual_machines.rst | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/source/adminguide/virtual_machines.rst
b/source/adminguide/virtual_machines.rst
index 0e463b96..04ae3da5 100644
--- a/source/adminguide/virtual_machines.rst
+++ b/source/adminguide/virtual_machines.rst
@@ -1191,6 +1191,22 @@ UEFI setting
- On KVM, it is recommended to set boot type to UEFI, and boot mode to SECURE.
- UEFI is required for some Windows versions.
+.. note::
+
+ **Recommendations for UEFI-based instances on KVM (volumes and NICs)**
+
+ UEFI-based instances on KVM may encounter PCI slot exhaustion when
attaching additional
+ volumes or network interfaces, due to high PCI device usage from the default
+ disk bus and NIC adapter selections. To avoid these issues:
+
+ - **Disk bus**: For Linux-based UEFI guests, it is recommended to use
**SCSI** as
+ the guest disk bus instead of VIRTIO. This reduces PCI device usage and
improves
+ support for attaching additional volumes.
+ - **NIC adapter**: Set the NIC adapter type to **e1000** for UEFI instances
to avoid
+ NIC attachment issues caused by PCI slot exhaustion.
+
+ Both of these settings can be configured in the **VM Settings** for an
instance.
+
|vm-settings-virtual-tpm-model-kvm.png|
TPM model for KVM. There are two options:
