[BUG] k3d should keep ip after restart

[vipcxj]

What did you do

• How was the cluster created?

k3d cluster create big-data \
  --image "srcr.proland.org.cn/sanrong/k3s:v1.33.5-k3s1-cuda-12.8.1-base-ubuntu22.04" \
  --gpus all \
  --agents 3 \
  --volume /data/k3d/big-data/local/server-0/:/var/lib/rancher/k3s/storage/@server:0 \
  --volume /data/k3d/big-data/local/agent-0/:/var/lib/rancher/k3s/storage/@agent:0 \
  --volume /data/k3d/big-data/local/agent-1/:/var/lib/rancher/k3s/storage/@agent:1 \
  --volume /data/k3d/big-data/local/agent-2/:/var/lib/rancher/k3s/storage/@agent:2 \
  -p "13880:80@loadbalancer" \
  -p "13443:443@loadbalancer" \
  --runtime-ulimit "nofile=655350:655350" \
  --runtime-ulimit "nproc=655350:655350" \
  --api-port 6550 \
  --registry-config ${CUR}/registries.yaml

• What did you do afterwards?
  nothing

What did you expect to happen

The k3d cluster should be ok after it restart

Screenshots or terminal output

time="2025-12-30T07:49:01Z" level=fatal msg="Failed to start networking: unable to initialize network policy controller: error getting node subnet: failed to find interface with specified node ip"

I think it's a bug related to #12844

Which OS & Architecture

arch: x86_64
cgroupdriver: systemd
cgroupversion: "2"
endpoint: /var/run/docker.sock
filesystem: extfs
infoname: node6
name: docker
os: Ubuntu 22.04.5 LTS
ostype: linux
version: 29.1.3

Which version of k3d

k3d version v5.8.3
k3s version v1.31.5-k3s1 (default)

Which version of docker

Client: Docker Engine - Community
 Version:           29.1.3
 API version:       1.52
 Go version:        go1.25.5
 Git commit:        f52814d
 Built:             Fri Dec 12 14:49:37 2025
 OS/Arch:           linux/amd64
 Context:           default

Server: Docker Engine - Community
 Engine:
  Version:          29.1.3
  API version:      1.52 (minimum version 1.44)
  Go version:       go1.25.5
  Git commit:       fbf3ed2
  Built:            Fri Dec 12 14:49:37 2025
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          v2.2.0
  GitCommit:        1c4457e00facac03ce1d75f7b6777a7a851e5c41
 runc:
  Version:          1.3.4
  GitCommit:        v1.3.4-0-gd6d73eb8
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

Client: Docker Engine - Community
 Version:    29.1.3
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.30.1
    Path:     /usr/libexec/docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v5.0.0
    Path:     /usr/libexec/docker/cli-plugins/docker-compose

Server:
 Containers: 35
  Running: 33
  Paused: 0
  Stopped: 2
 Images: 95
 Server Version: 29.1.3
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Using metacopy: false
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: systemd
 Cgroup Version: 2
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local splunk syslog
 CDI spec directories:
  /etc/cdi
  /var/run/cdi
 Swarm: inactive
 Runtimes: runc io.containerd.runc.v2 nvidia
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 1c4457e00facac03ce1d75f7b6777a7a851e5c41
 runc version: v1.3.4-0-gd6d73eb8
 init version: de40ad0
 Security Options:
  apparmor
  seccomp
   Profile: builtin
  cgroupns
 Kernel Version: 6.8.0-90-generic
 Operating System: Ubuntu 22.04.5 LTS
 OSType: linux
 Architecture: x86_64
 CPUs: 32
 Total Memory: 124.9GiB
 Name: node6
 ID: 226fce35-5ef7-4318-8b16-741d82458f4f
 Docker Root Dir: /data/docker
 Debug Mode: false
 Experimental: false
 Insecure Registries:
  ::1/128
  127.0.0.0/8
 Registry Mirrors:
  https://dockerhub.proland.org.cn/
 Live Restore Enabled: false
 Firewall Backend: iptables

[vipcxj]

Although the related issue was closed, the problem was never actually fixed, and the k3s developers have said they don't plan to support dynamic IPs in the future, so k3d must ensure static IPs