On May 19, 2026, KUSANAGI added support for Nginx 1.31. As a result, the default version used by the kusanagi init command has been changed to Nginx 1.31.
Please refer to the following release information for details:
KUSANAGI 9.8.11-1（KUSANAGI 9, Business Edition, Page Speed Technology）
KUSANAGI Security Edition 10.3.15-1.el9
In addition, KUSANAGI Security Edition now supports zero-downtime upgrades through SafeUpgrade.
For upgrade procedures, please refer to the “Nginx SafeUpgrade Quick Start” guide.