Limitations and deprecated features

Last published : Sep 30, 2026
This document describes the unsupported features, system limitations, and deprecated features in the NetScaler® 15.1 Tech Preview. Feature gaps and hypervisor limitations apply.

Unsupported NetScaler features

The following NetScaler features are not supported in this release:
  • NextGen API
  • Front End Optimization (FEO)
  • Autosave of the running configuration
  • IPsec protocol
  • Layer 3 cluster
  • Link Aggregation Control Protocol (LACP) on NetScaler VPX™ for Linux running on ESXi or KVM
  • The maximum number of admin partitions supported is 250
  • Integrated Caching
  • Jumbo frame support is unavailable on the following drivers: igb, ixgbe, netvsc, af_packet, and ena.

System limitations

The following system limitations apply in this release:
  • Preboot user data for GCP
  • The nsapimgr call options are partially supported. For the supported nsapimgr call options, see FAQs.
  • The what utility

Boot failure after upgrade on Linux KVM

Note:
This workaround applies to Linux KVM only.
If the appliance does not boot after you upgrade to Linux, complete the following steps:
  1. Power off the VM.
  2. Check the CPU model. If it is set to qemu64 or kvm64, update the CPU model to host-passthrough:
    • Libvirt domain XML: <cpu mode='host-passthrough'/>
    • virt-install: --cpu host-passthrough
  3. Power on the VM.

Deprecated features

The following features are deprecated in this release:
  • Routing Information Protocol (RIP)
  • Routing Information Protocol next generation (RIPng)
  • Intermediate System to Intermediate System (IS-IS) protocol
  • Precision Time Protocol (PTP)
  • File Transfer Protocol (FTP)
  • Telnet