Virtual Software Tiers (VST)
In the world of IBM i, software licensing has traditionally been tied to the physical characteristics of hardware — namely processor performance and server capacity. But as more organizations shift toward cloud-native strategies and virtualized environments, IBM has introduced Virtual Software Tiers
What Are Virtual Software Tiers?
Virtual Software Tiers (VSTs) are a licensing model from IBM that lets customers purchase IBM i software licenses based on virtualized workloads instead of physical machine characteristics.
Rather than linking software tiers to physical processor power, we can now license based on your allocated virtual processing capacity — the actual system resources your partition uses.
Traditionally, software tiers were tied directly to the physical hardware’s model and performance characteristics. While this method works well for on-premises environments, it quickly became a limiting factor as organizations embraced more modern IT strategies, such as:
- Cloud environments (e.g., IBM Power Virtual Server)
- Multi-tenant hosting
- Flexible LPAR deployment and resizing
- Metered or subscription-based billing models
With VSTs, licensing becomes more aligned with actual usage, enabling smoother workload portability and right-sized spending. In PowerVS, virtual software Tiers are supported for P10 systems and above and IBMi versions 7.3 and above
Benefits of Virtual Software Tiers
- · Cost Efficiency: Only pay for the compute capacity your application actually needs. Especially useful for test/dev environments or lightweight business apps.
- Cloud-Native Compatibility: PowerVS users benefit directly, as IBM i workloads can now be licensed based on their cloud-assigned virtual resources, not the underlying hardware.
How it works
Imagine you're running an IBM i workload on a Power10 server, but the application only requires 0.5 processor capacity. Under the traditional licensing model, you'd still have to purchase a license based on the full server tier, leading to additional costs and operational complexity. For configuring Virtual Software Tiers (VST) in IBM PowerVS, users are provided with the flexibility to either auto assign a Virtual Serial Number (VSN) or reuse a retained VSN from a previously deleted virtual machine. Get more details from https://cloud.ibm.com/docs/power-iaas?topic=power-iaas-ibmi-vsw-tiers
With Virtual Software Tiers, we can now:
- Assign a Virtual Serial Number (VSN) for workload portability
- License only the 0.5 processing capacity by adding software tier for the virtual serial number (P05, P10, P20, P30)
- Seamlessly move the partition to a Power10 server or IBM PowerVS Cloud — without needing to relicense
Virtual software tier configuration Limits for cores and memory
|
Software Tier
|
Maximum virtual processors
|
Maximum memory
|
|
P05
|
1
|
64 GB
|
|
P10
|
4
|
1 TB
|
|
P20
|
12
|
1 TB
|
|
P30
|
MAX (no limit)
|
MAX (no limit)
|
Virtual software tier supported systems
|
System Type
|
P05 supported?
|
P10 supported?
|
P20 supported?
|
P30 supported?
|
|
S1022
|
Yes
|
Yes
|
No
|
No
|
|
S1122
|
Yes
|
Yes
|
Yes
|
No
|
|
E1080
|
No
|
Yes
|
Yes
|
Yes
|
|
E1180
|
No
|
Yes
|
Yes
|
Yes
|
|
E1050
(doesn’t support IBM i)
|
N/A
|
N/A
|
N/A
|
N/A
|
|
E1150
(doesn’t support IBM i)
|
N/A
|
N/A
|
N/A
|
N/A
|
Creating a VM with virtual software tier
- Assigning virtual serial number(VSN) to the VM
Assigning Software tier for the existing IBMi VM
- Existing IBMi VM, assign virtual serial number
Once VSN is assigned , software tier will be defaulted to the system maximum supported tier (P10 for S1022, P20 for S1122, P30 for E1080/E1180)
- Modify the software tier to the required tier
Billing
IBMi OS and licenses will be billed according to the software tier of the VM
Billing for the VM
