Network Express in direct mode
You can configure the entire Network Express adapter in the IOCDS or DPM in direct mode (NETD).
With a Network Express adapter in direct mode, you can define one physical function of type Network Express direct (NETD PF) and multiple virtual functions (NETD VFs) per PCHID. You cannot define NETH PCI functions or OSH devices on any PCHID of a Network Express adapter in direct mode.
NETD is a single root I/O virtualization (SR-IOV) capable device. With NETD, the partition that owns the physical function (PF) controls it. The LPAR can use features such as VLAN tagging and hardware offloads. Each VF can be assigned to a different guest or LPAR. Each VF shares the PF's resources, but has its own independent configuration. You manage features at the VF level, which enables precise setup. Be aware of the functions available, and use them with care.
NETD supports up to 127 VFs.
Using NETD with z/VM and KVM
You can attach a NETD pass-through VF to a z/VM guest, but you cannot assign a PF directly to z/VM. In a KVM environment, you assign the PF (for switchdev mode and offloads) to the host and dedicate VFs to guests.
Common use cases
- SR-IOV networking:
- Pass Ethernet devices through to guest operating systems or containers. For example, Linux bridge or Open vSwitch with hardware offloads.
- Cloud and network frameworks:
- Integrated SR-IOV plug-ins in Kubernetes or OpenStack for accelerated networking.
- Hybrid assignments:
- Allocate the PF to one partition and VFs to other systems, such as z/VM guests, KVM guests, or
other LPARs. Actions that are taken on the PF affect the other systems.Note: In DPM, this hybrid assignment is not supported.
- Single-system switch:
- Assign both PF and all VFs to one LPAR or host to run an Open vSwitch or similar, using switchdev mode to offload bridge functions onto the adapter.