[2.3.0] Checkmk Werk 16661 created: Notification Spooler: Support IPv6

[//]: # (werk v2) # Notification Spooler: Support IPv6 key | value ---------- | --- date | 2024-06-18T06:24:52+00:00 version | 2.3.0p8 class | feature edition | cee component | notifications level | 1 compatible | yes Previously mknotifyd only supported IPv4. This werk adds support for IPv6. Incoming connections now accept IPv4 and IPv6 if the server supports dual-stack IPv6. For outgoing connections you may now enter IPv6 addresses as well. IPv6 will also be used, if a hostname resolves to an IPv6 address. If a hostname resolves to both IPv4 and IPv6, IPv4 is still preferred.