[BUG] Lookup timeout, broken DNS in cluster

[tim-reply]

What did you do

• How was the cluster created?

  • k3d cluster create mycluster -p "8000:80@loadbalancer"

• What did you do afterwards?

  • uploaded some images (using skaffold, so I guess several "k3d image import")
  • machine have rebooted, went to suspend a bunch and back
  • eventually I start get this error whenever trying to deploy new pods that need images from internet: dial tcp: lookup registry-1.docker.io on 127.0.0.11:53: read udp 127.0.0.1:41970->127.0.0.11:53: i/o timeout (this is from events on pod, which is in image pull back-off state)
  • at the same time resolving docker.io from the host works fine
  • then I restart cluster by k3d cluster stop mycluster and k3d cluster start mycluster
  • after that the issue goes away (restarting only coredns does not help unfortunately)

What did you expect to happen

Cluster keeps working as usual, names are resolved ok without the need of cluster restart.

Which OS & Architecture

arch: x86_64
cgroupdriver: cgroupfs
cgroupversion: "1"
endpoint: /var/run/docker.sock
filesystem: extfs
infoname: t480s
name: docker
os: Ubuntu 20.04.1 LTS
ostype: linux
version: 24.0.6

Which version of k3d

k3d version v5.4.9
k3s version v1.25.7-k3s1 (default)

Which version of docker

Client: Docker Engine - Community
 Version:           24.0.6
 API version:       1.43
 Go version:        go1.20.7
 Git commit:        ed223bc
 Built:             Mon Sep  4 12:32:12 2023
 OS/Arch:           linux/amd64
 Context:           default

Server: Docker Engine - Community
 Engine:
  Version:          24.0.6
  API version:      1.43 (minimum version 1.12)
  Go version:       go1.20.7
  Git commit:       1a79695
  Built:            Mon Sep  4 12:32:12 2023
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.6.24
  GitCommit:        61f9fd88f79f081d64d6fa3bb1a0dc71ec870523
 runc:
  Version:          1.1.9
  GitCommit:        v1.1.9-0-gccaecfc
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0
  
  
  Client: Docker Engine - Community
 Version:    24.0.6
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.11.2
    Path:     /usr/libexec/docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v2.21.0
    Path:     /usr/libexec/docker/cli-plugins/docker-compose
  scan: Docker Scan (Docker Inc.)
    Version:  v0.23.0
    Path:     /usr/libexec/docker/cli-plugins/docker-scan

Server:
 Containers: 54
  Running: 2
  Paused: 0
  Stopped: 52
 Images: 700
 Server Version: 24.0.6
 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: cgroupfs
 Cgroup Version: 1
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 61f9fd88f79f081d64d6fa3bb1a0dc71ec870523
 runc version: v1.1.9-0-gccaecfc
 init version: de40ad0
 Security Options:
  apparmor
  seccomp
   Profile: builtin
 Kernel Version: 5.15.0-86-generic
 Operating System: Ubuntu 20.04.1 LTS
 OSType: linux
 Architecture: x86_64
 CPUs: 8
 Total Memory: 15.36GiB
 Name: t480s
 ID: JPJP:2FZY:W3AU:Y3AW:SKMJ:XUSY:4PJH:ZBJR:KD3H:S73K:Z6LA:P3PI
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Experimental: false
 Insecure Registries:
  docker-registry.localhost:8081
  127.0.0.0/8
 Live Restore Enabled: false