Aspen Mesh Platform 1.21.6-am4 release notes#

Introduction#

These release notes describe the differences between Aspen Mesh 1.21.6-am2 and 1.21.6-am4.

Supported container-orchestration platforms#

This release is officially supported on these container-orchestration platforms and versions:

Platform

Version

Recommended Helm version

Kubernetes

1.34

3.19

Kubernetes

1.33

3.18

Kubernetes

1.26

3.14

Kubernetes

1.27

3.15

Kubernetes

1.28

3.16

Kubernetes

1.29, 1.32

3.17

OpenShift

4.14

3.15

OpenShift

4.16

3.17

OpenShift

4.18

3.19

Istio proxy (Envoy) version#

1.29.12

Security updates#

Istio#

(No security updates)

Istio proxy (Envoy)#

(No security updates)

Aspen Mesh Platform features#

(No security updates)

Other changes#

Istio#

  • ASM-5329: (Backport from open source Istio 1.27) Fixed a case-insensitivity issue that caused Istio to reject host routing when the same hostname appeared in mixed case across multiple VirtualServices.

Aspen Mesh Platform features#

  • ASM-5331: Added EDNS0 (RFC 6891) support for larger UDP responses , reducing TCP fallback and improving query performance. In the override values file for the DNS controller, configure .Edns0Support to enable or disable EDNS0 feature and .Edns0PayloadSize to set a custom payload size; defaults are true and 1232, respectively.

Known issues#

  • ASM-5534: On dual-stack (IPv4+IPv6) clusters, Istiod crashes when any of the hosts listed in a service entry’s .spec.hosts field include uppercase letters. Although DNS names are case-insensitive, the relevant code dereferences a nil pointer and causes the crash or a restart loop in Istiod.

    To work around this issue, make sure the names of all hosts are lowercase.

    Note

    Fixed this issue in 1.21.6-am4-EHF, which was released on January 30, 2026.