Kubernetes on FreeBSD with Linux worker nodes and Cilium
This is the second part in a series where I describe how I set up a Kubernetes cluster on FreeBSD in my homelab. If there happen to be anyone worried that I’ve abandoned illumos — do not fear! I happen to enjoy working in anything illumos, Linux and BSD based… well, some of the “BSD” a bit less than the others — choosing A Poor File System (aka APFS) instead of ZFS seemed like a mistake in my viewpoint, Apple — I’m looking at you. I prefer the FFS in OpenBSD or NetBSD before APFS, but FreeBSD with OpenZFS is my top choice.
In the plans are to write down what I demoed a while ago on auto-join for worker nodes, and that will be in illumos. In the brain buffer there’s some BGP related stuff as well, as more containerlab. A dozen of Kubernetes related projects that also should be dumped into words. And it’s possible that I might have another announcement that I want to make before the summer.
Demo on YouTube around the concept
I recorded a demo of this concept on YouTube, and during creation of that demo I found some minor typos that I’ve now revised in the first article:
The demo were intended to describe the first part, standing up a Kubernetes Control Plane in FreeBSD, but it seemed very thin to only do the components that literally just takes some minute. Hence, I decided to also add a working Data Plane prior to recording a video.
Basically the steps are as follows
- Creating the control plane as described in part 1
- Download a cloud-image
- Create storage backend to the guest
- Establish a cloud-init provisioner
- bootstrap the guest
- Create a template out of a snapshot taken from the guest
- bootstrap worker nodes from the template
Download a cloud-image
One Kubernetes friendly distribution of choice is Ubuntu and their Jammy 22.04 LTS images are great for cloud-init and bhyve.
cd /var/tmp
curl -LO https://cloud-images.ubuntu.com/jammy/current/jammy-server-cloudimg-amd64.img
qemu-img convert -O raw jammy-server-cloudimg-amd64.img jammy-server-cloudimg-amd64.img.raw
Create storage backend to the guest
As the storage backend we will create a ZVOL
zfs create -V 10G -s -p dpool/bhyve/${guest}/rootEstablish a cloud-init provisioner for bhyve
9pfs as the shared storage
I’m used to run workloads with bhyve in illumos, but running it in FreeBSD was a rather new concept for me and at first I looked into vm-bhyve (and then the other bhyve related frontends available in FreeBSD), but they felt overly complicated for what I were going to use. Also they seemed to lack the support for cloud-init I needed for my project, so I went with vanilla bhyve instead.
Some year ago I would’ve proposed NFS as a shared storage between the hosts (both hypervisor and guests), but as of recently I’ve switch over to the Plan 9 protocols instead, which does this in a elegant fashion with the 9pfs.
9pfs just needs a directory of choice at the hypervisor, a configuration in bhyve and then the mount command within the guest and that’s it.
cloud-init from a NoCloud Metadata Server
In illumos I’m used to mount an ISO9660 with the related files by pointing to a user-data file from the zadm command and I have everything I need. But for some reason I had trouble enabling it in the FreeBSD implementation, even copying over a working seed image from my illumos hypervisors. But for the better good I decided to implement a NoCloud Metadata Server instead, as that actually simplified some of the stuff (but in turn introduced other, solvable, issues).
Initialize the NoCloud Metadata Server (seriously) by typing this in a shell:
mkdir /var/tmp/cloud-init
cd /var/tmp/cloud-init
python3.9 -m http.serverSome minor issues
During the boot there will be some expected issues that not affects the end result, such as:
[ 22.107415] cloud-init[576]: 2024-01-12 06:35:43,750 - activators.py[WARNING]: Running ['netplan', 'apply'] resulted in stderr output:
[ 22.110197] cloud-init[576]: ** (generate:592): WARNING **: 08:35:33.847: Permissions for /etc/netplan/50-cloud-init.yaml are too open. Netplan configuration should NOT be access
ible by others.
[ 22.114005] cloud-init[576]: WARNING:root:Cannot call Open vSwitch: ovsdb-server.service is not running.
[ 22.116134] cloud-init[576]: ** (process:590): WARNING **: 08:35:34.356: Permissions for /etc/netplan/50-cloud-init.yaml are too open. Netplan configuration should NOT be accessi
ble by others.
[ 22.120060] cloud-init[576]: ** (process:590): WARNING **: 08:35:34.590: Permissions for /etc/netplan/50-cloud-init.yaml are too open. Netplan configuration should NOT be accessi
ble by others.
[ 22.123866] cloud-init[576]: ** (process:590): WARNING **: 08:35:34.591: Permissions for /etc/netplan/50-cloud-init.yaml are too open. Netplan configuration should NOT be accessi
ble by others.
[ 22.127606] cloud-init[576]: Failed to connect system bus: No such file or directory
[ 22.129400] cloud-init[576]: WARNING:root:Falling back to a hard restart of systemd-networkd.service
[ 22.264892] cloud-init[576]: 2024-01-12 06:35:43,932 - schema.py[WARNING]: Invalid cloud-config provided: Please run 'sudo cloud-init schema --system' to see the schema errors.
[ OK ] Stopped Wait for Network to be Configured. I’m not sure if it is the NoCoud provider or Ubuntu that causes this issue but we try to handle it in the cloud-config.
Another issue, or rather feature, from running the Metadata Server is that the guest requires a DHCP (due to the nature of the guest communicating over IP), but we only use DHCP for bootstrap and then puts a static configuration in place.
First boot / guest template
Create a password hash, i.e. by typing:
pwdhash=$(openssl passwd -6)It is optional to create a template, but I felt that it was far too much time spent waiting and opted for a quicker way. Create a template similar to the following, according to your needs. Whatever you put in there stays in there.
What this does is that it creates a ZVOL backend, puts the cloud-image onto the raw disk, installs Kubernetes. Generates a cloud-init configuration to the NoCloud Metadata Server.
#!/usr/bin/env bash
guest=${1}
zpool=dpool
zfs create -V 10G -s -p ${zpool}/bhyve/${guest}/root
pv /var/tmp/jammy-server-cloudimg-amd64-disk-kvm.img.raw > /dev/zvol/${zpool}/bhyve/${guest}/root
uuid=$(uuidgen)
cinitdir=/var/tmp/cloud-init/${guest}
cinitip=192.168.168.1
certdir=/var/tmp/k8sbsd
sharedir=${certdir}/p9share/
mkdir -p ${cinitdir} ${sharedir}
bridge=bridge32
iface=${guest##*[^[:digit:]]}
ifconfig tap${iface} create up
ifconfig ${bridge} addm tap${iface}
cat << EOF > ${cinitdir}/meta-data
instance-id: ${uuid}
local-hostname: ${guest}
EOF
cat << EOF > ${cinitdir}/user-data
#cloud-config
users:
- name: kubernaut
gecos: Captain Kube
primary_group: users
groups: users
shell: /bin/bash
expiredate: '2029-12-31'
lock_passwd: false
sudo: ALL=(ALL) NOPASSWD:ALL
passwd: ${pwdhash}
bootcmd:
- systemctl disable --now systemd-networkd-wait-online
ntp:
enabled: true
timezone: Europe/Stockholm
manage_resolv_conf: true
mounts:
- [ shared, /var/shared, 9p, "rw,relatime,dirsync,uname=root,cache=mmap,access=client,trans=virtio,_netdev", "0", "0" ]
resolv_conf:
nameservers: ['9.9.9.9', '1.1.1.1']
searchdomains:
- cloud.mylocal
domain: cloud.mylocal
options:
rotate: true
timeout: 1
write_files:
- path: /etc/sysctl.d/enabled_ipv4_forwarding.conf
content: |
net.ipv4.conf.all.forwarding=1
- path: /etc/modules-load.d/crio.conf
content: |
overlay
br_netfilter
- path: /home/kubernaut/.bash_profile
content: |
if [ ! -f /usr/bin/resize ]; then
resize() {
old=$(stty -g)
stty -echo
printf '\033[18t'
IFS=';' read -d t _ rows cols _
stty "$old"
stty cols "$cols" rows "$rows"
}
fi
if [ "$(tty)" = "/dev/ttyS0" ]; then
resize
fi
append: true
- path: /root/.bash_profile
content: |
if [ ! -f /usr/bin/resize ]; then
resize() {
old=$(stty -g)
stty -echo
printf '\033[18t'
IFS=';' read -d t _ rows cols _
stty "$old"
stty cols "$cols" rows "$rows"
}
fi
if [ "$(tty)" = "/dev/ttyS0" ]; then
resize
fi
append: true
- path: /etc/sysctl.d/99-kubernetes-cri.conf
content: |
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
- path: /etc/sysctl.d/99-override_cilium_rp_filter.conf
content: |
net.ipv4.conf.lxc*.rp_filter = 0
- path: /var/lib/kubelet/kubelet-config.yaml
content: |
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
cgroupDriver: systemd
authentication:
anonymous:
enabled: false
webhook:
enabled: true
x509:
clientCAFile: "/var/lib/kubelet/ca.pem"
authorization:
mode: Webhook
clusterDomain: "cluster.local"
clusterDNS:
- "10.96.0.10"
resolvConf: "/run/systemd/resolve/resolv.conf"
runtimeRequestTimeout: "15m"
tlsCertFile: "/var/lib/kubelet/worker.pem"
tlsPrivateKeyFile: "/var/lib/kubelet/worker-key.pem"
- path: /etc/systemd/system/kubelet.service
content: |
[Unit]
Description=Kubernetes Kubelet
Documentation=https://github.com/kubernetes/kubernetes
After=crio.service
Requires=crio.service
[Service]
ExecStart=/usr/bin/kubelet \
--config=/var/lib/kubelet/kubelet-config.yaml \
--container-runtime-endpoint=/var/run/crio/crio.sock \
--kubeconfig=/var/lib/kubelet/kubeconfig \
--register-node=true \
--v=2
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
runcmd:
- modprobe overlay
- modprobe br_netfilter
- sysctl --system 2>/dev/null
- echo "deb [signed-by=/usr/share/keyrings/libcontainers-archive-keyring.gpg] https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable/xUbuntu_22.04/ /" > /etc/apt/sources.list.d/devel:kubic:libcontainers:stable.list
- echo "deb [signed-by=/usr/share/keyrings/libcontainers-crio-archive-keyring.gpg] https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable:/cri-o:/1.28/xUbuntu_22.04/ /" > /etc/apt/sources.list.d/devel:kubic:libcontainers:stable:cri-o:1.28.list
- mkdir -p /usr/share/keyrings /var/lib/kubelet
- curl -L https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable/xUbuntu_22.04/Release.key | gpg --dearmor -o /usr/share/keyrings/libcontainers-archive-keyring.gpg
- curl -L https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable:/cri-o:/1.28/xUbuntu_22.04/Release.key | gpg --dearmor -o /usr/share/keyrings/libcontainers-crio-archive-keyring.gpg
- curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.29/deb/Release.key | sudo gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg
- echo 'deb [signed-by=/etc/apt/keyrings/kubernetes-apt-keyring.gpg] https://pkgs.k8s.io/core:/stable:/v1.29/deb/ /' | sudo tee /etc/apt/sources.list.d/kubernetes.list
- export DEBIAN_FRONTEND=noninteractive KUBECONFIG=/etc/kubernetes/admin.conf
- DEBIAN_FRONTEND=noninteractive apt-get update -q -y
- DEBIAN_FRONTEND=noninteractive apt-get install -y cri-o cri-o-runc apt-transport-https ca-certificates curl gnupg-agent software-properties-common jq golang-cfssl
- systemctl daemon-reload
- systemctl enable --now crio
- DEBIAN_FRONTEND=noninteractive apt-get install -q -y kubelet=1.29.0-1.1 kubectl=1.29.0-1.1
- DEBIAN_FRONTEND=noninteractive apt-mark hold kubelet kubectl
EOF
cat << EOF > ${guest}.cfg
acpi_tables=false
acpi_tables_in_memory=true
memory.size=4G
x86.strictmsr=true
x86.vmexit_on_hlt=true
lpc.fwcfg=bhyve
lpc.com1.path=stdio
lpc.bootrom=/usr/local/share/uefi-firmware/BHYVE_UEFI.fd
cpus=4
pci.0.0.0.device=hostbridge
pci.0.0.0.model=i440fx
pci.0.3.0.device=ahci
pci.0.4.0.device=virtio-blk
pci.0.4.0.path=/dev/zvol/dpool/bhyve/${guest}/root
pci.0.5.0.device=virtio-net
pci.0.5.0.backend=tap${iface}
pci.0.6.0.device=virtio-9p
pci.0.6.0.sharename=shared
pci.0.6.0.path=/var/tmp/k8sbsd/p9share
pci.0.30.0.device=fbuf
pci.0.30.0.vga=off
pci.0.30.0.unix=/tmp/${guest}.vnc
pci.0.30.1.device=xhci
pci.0.30.1.slot.1.device=tablet
pci.0.31.0.device=lpc
system.serial_number=ds=nocloud;s=http://${cinitip}:8000/${guest};i=${uuid}
name=${guest}
EOF
bhyve -k ${guest}.cfgIn a dedicated terminal (my recommendation is to utilize tmux, I’ve yet to understand how to escape from guests in FreeBSD. In illumos I run each bhyve guest in a dedicated non-global zone which in this case would correspond to a VNET jail. Maybe for later exercise to figure that out. Anyway, with tmux I found life in FreeBSD to be easier.
Boot the guest with a template name in the style of name+digit, i.e. worker0, as the argument to the script. This will create a tap interface with the same number.
As the guest is booting up the first time, login and become root and type the following, so that cloud-init will run again on the next boot:
cloud-init clean
systemctl poweroffThen, create the snapshot and clone it:
zpool=dpool
zfs clone ${zpool}/bhyve/${guest}/root@init ${zpool}/bhyve/worker-init
zfs promote ${zpool}/bhyve/worker-init@initCreate a worker node bootstrap script
The actual workers will be created out of a cloned snapshot. The cloud-init will be similar, but with some differences. In this template we start by creating a storage backend out of the clone. Then we will generate the certificates on the host and copy them to the shared file system (which we will consume by the guest during boot). Another thing we’ll do, is that we’ll replace the DHCP lease with a static address (this is very hackish, but it see to do the job and we want results without over achieving, right?!) and finally we configure the kubelet to the right configuration by utilizing the 9P file system. I think this is rather neat.
In a terminal (such as tmux), save the following and it as root:
#!/usr/bin/env bash
guest=${1}
zpool=dpool
cinitip=192.168.168.1
SSHKEY=<ssh-ed25519... > # optional SSH key
zfs create -p dpool/bhyve/${guest}
zfs clone dpool/bhyve/jammy-init@init dpool/bhyve/${guest}/root
uuid=$(uuidgen -r)
cinitdir=/var/tmp/cloud-init/${guest}
certdir=/var/tmp/k8sbsd
sharedir=${certdir}/p9share/
mkdir -p ${cinitdir} ${sharedir}
bridge=bridge32
iface=${guest##*[^[:digit:]]}
ifconfig tap${iface} create up
ifconfig ${bridge} addm tap${iface}
echo "192.168.168.2${iface} ${guest}" >> /opt/local/jails/containers/apiserv/etc/hosts
cp ${certdir}/kubernetes-ca/kubernetes-ca.pem ${sharedir}/ca.pem
cat << EOF > ${sharedir}/${guest}-csr.json
{
"CN": "system:node:${guest}",
"key": {
"algo": "rsa",
"size": 2048
},
"hosts": [
"${guest}",
"192.168.168.2${iface}"
],
"names": [
{
"O": "system:nodes"
}
]
}
EOF
cfssl gencert -ca=${certdir}/kubernetes-ca/kubernetes-ca.pem -ca-key=${certdir}/kubernetes-ca/kubernetes-ca-key.pem --config=${certdir}/kubernetes-ca/kubernetes-ca-config.json -profile=client -profile=kubelet ${sharedir}/${guest}-csr.json | cfssljson -bare ${sharedir}/${guest}
touch ${sharedir}/${guest}.kubeconfig
KUBECONFIG=${sharedir}/${guest}.kubeconfig kubectl config set-cluster default-cluster --server=https://192.168.168.10:6443 --certificate-authority ${certdir}/kubernetes-ca/kubernetes-ca.pem --embed-certs
KUBECONFIG=${sharedir}/${guest}.kubeconfig kubectl config set-credentials system:node:${guest} --client-key ${sharedir}/${guest}-key.pem --client-certificate ${sharedir}/${guest}.pem --embed-certs
KUBECONFIG=${sharedir}/${guest}.kubeconfig kubectl config set-context default-system --cluster default-cluster --user system:node:${guest}
KUBECONFIG=${sharedir}/${guest}.kubeconfig kubectl config use-context default-system
cat << EOF > ${cinitdir}/meta-data
instance-id: ${uuid}
local-hostname: ${guest}
EOF
cat << EOF > ${cinitdir}/user-data
#cloud-config
users:
- name: kubernaut
gecos: Captain Kube
primary_group: users
groups: users
shell: /bin/bash
ssh_authorized_keys: [ ${SSHKEY} ]
expiredate: '2029-12-31'
lock_passwd: false
sudo: ALL=(ALL) NOPASSWD:ALL
passwd: ${pwdhash}
bootcmd:
- systemctl disable --now systemd-networkd-wait-online
- chmod og-r /etc/netplan/50-cloud-init.yaml
- |
sed -i 's/dhcp4\: true$/addresses:\n - 192.168.168.2${iface}\/24\n routes:\n - to: default\n via: 192.168.168.254\n nameservers:\n addresses:\n - 1.1.1.1\n - 8.8.8.8/g' /etc/netplan/50-cloud-init.yaml
- netplan apply
ntp:
enabled: true
timezone: Europe/Stockholm
manage_resolv_conf: true
mounts:
- [ shared, /var/shared, 9p, "rw,relatime,dirsync,uname=root,cache=mmap,access=client,trans=virtio,_netdev", "0", "0" ]
resolv_conf:
nameservers: ['9.9.9.9', '1.1.1.1']
searchdomains:
- cloud.mylocal
domain: cloud.mylocal
options:
rotate: true
timeout: 1
write_files:
- path: /etc/sysctl.d/enabled_ipv4_forwarding.conf
content: |
net.ipv4.conf.all.forwarding=1
- path: /etc/modules-load.d/crio.conf
content: |
overlay
br_netfilter
- path: /home/kubernaut/.bash_profile
content: |
if [ ! -f /usr/bin/resize ]; then
resize() {
old=\$(stty -g)
stty -echo
printf '\033[18t'
IFS=';' read -d t _ rows cols _
stty "\$old"
stty cols "\$cols" rows "\$rows"
}
fi
if [ "/dev/pts/8" = "/dev/ttyS0" ]; then
resize
fi
append: true
- path: /root/.bash_profile
content: |
if [ ! -f /usr/bin/resize ]; then
resize() {
old=\$(stty -g)
stty -echo
printf '\033[18t'
IFS=';' read -d t _ rows cols _
stty "\$old"
stty cols "\$cols" rows "\$rows"
}
fi
if [ "/dev/pts/8" = "/dev/ttyS0" ]; then
resize
fi
append: true
- path: /etc/sysctl.d/99-kubernetes-cri.conf
content: |
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
net.bridge.bridge-nf-call-ip6tables = 1
- path: /etc/sysctl.d/99-override_cilium_rp_filter.conf
content: |
net.ipv4.conf.lxc*.rp_filter = 0
- path: /var/lib/kubelet/kubelet-config.yaml
content: |
kind: KubeletConfiguration
apiVersion: kubelet.config.k8s.io/v1beta1
cgroupDriver: systemd
authentication:
anonymous:
enabled: false
webhook:
enabled: true
x509:
clientCAFile: "/var/lib/kubelet/ca.pem"
authorization:
mode: Webhook
clusterDomain: "cluster.local"
clusterDNS:
- "10.96.0.10"
resolvConf: "/run/systemd/resolve/resolv.conf"
runtimeRequestTimeout: "15m"
tlsCertFile: "/var/lib/kubelet/worker.pem"
tlsPrivateKeyFile: "/var/lib/kubelet/worker-key.pem"
- path: /etc/systemd/system/kubelet.service
content: |
[Unit]
Description=Kubernetes Kubelet
Documentation=https://github.com/kubernetes/kubernetes
After=crio.service
Requires=crio.service
[Service]
ExecStart=/usr/bin/kubelet \
--config=/var/lib/kubelet/kubelet-config.yaml \
--container-runtime-endpoint=/var/run/crio/crio.sock \
--kubeconfig=/var/lib/kubelet/kubeconfig \
--register-node=true \
--v=2
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
runcmd:
- ln -s /var/shared/ca.pem /var/lib/kubelet/ca.pem
- ln -s /var/shared/\$(cat /etc/hostname).kubeconfig /var/lib/kubelet/kubeconfig
- ln -s /var/shared/\$(cat /etc/hostname).pem /var/lib/kubelet/worker.pem
- ln -s /var/shared/\$(cat /etc/hostname)-key.pem /var/lib/kubelet/worker-key.pem
- systemctl restart kubelet
EOF
cat << EOF > ${guest}.cfg
acpi_tables=false
acpi_tables_in_memory=true
memory.size=4G
x86.strictmsr=true
x86.vmexit_on_hlt=true
lpc.fwcfg=bhyve
lpc.com1.path=stdio
lpc.bootrom=/usr/local/share/uefi-firmware/BHYVE_UEFI.fd
cpus=4
pci.0.0.0.device=hostbridge
pci.0.0.0.model=i440fx
pci.0.3.0.device=ahci
pci.0.4.0.device=virtio-blk
pci.0.4.0.path=/dev/zvol/dpool/bhyve/${guest}/root
pci.0.5.0.device=virtio-net
pci.0.5.0.backend=tap${iface}
pci.0.6.0.device=virtio-9p
pci.0.6.0.sharename=shared
pci.0.6.0.path=/var/tmp/k8sbsd/p9share
pci.0.31.0.device=lpc
system.serial_number=ds=nocloud;s=http://${cinitip}:8000/${guest};i=${uuid}
name=${guest}
EOF
bhyve -k ${guest}.cfgFinally, bootstrapping worker nodes
Bootstrap one worker node
./create_worker.sh worker1Within some 15–60 seconds (? depending on hardware and communications), a worker node should be up and running.
/var/tmp/k8sbsd]# kubectl get nodes
NAME STATUS ROLES AGE VERSION
worker1 Ready <none> 2s v1.29.0Bootstrap some more worker nodes
In new terminals, repeat the bootstrap to have some more worker nodes. I believe that I should checkout the cu command for that console handling as a future exercise.
Install Core DNS
Verify that the gsed is installed (or adapt the sed):
curl -s https://raw.githubusercontent.com/coredns/deployment/master/kubernetes/coredns.yaml.sed | gsed '/^\s*forward . UPSTREAMNAMESERVER {$/{:a;N;/^\s*}$/M!ba;d};s/CLUSTER_DNS_IP/10.96.0.10/g;s/CLUSTER_DOMAIN REVERSE_CIDRS/cluster.local in-addr.arpa ip6.arpa/g;s/}STUBDOMAINS/}/g;s/# replicas:/replicas: 2 #/g' |kubectl create -f -Install Cilium
Either compile helm or cilium-cli commands (but the Cilium CLI command is to prefer as it also benefits from useful features around status and is a neat tool to have.
cilium version
cilium-cli: v0.15.19 compiled with go1.21.5 on freebsd/amd64
cilium image (default): v1.14.4
cilium image (stable): v1.14.5
cilium image (running): 1.14.5Install Cilium CNI in the kube-proxy free setup (as we don’t have any kube-proxy at all in place).
cilium install --version 1.14.5 \
--set kubeProxyReplacement=true \
--set k8sServiceHost=192.168.168.10 \
--set k8sServicePort=6443 \
--set hubble.relay.enabled=true \
--set hubble.ui.enabled=true # --wait (optionally)Some two minutes the cluster is installed, and check the status with the cilium status command:
cilium status
/¯¯\
/¯¯\__/¯¯\ Cilium: OK
\__/¯¯\__/ Operator: OK
/¯¯\__/¯¯\ Envoy DaemonSet: disabled (using embedded mode)
\__/¯¯\__/ Hubble Relay: OK
\__/ ClusterMesh: disabled
Deployment hubble-ui Desired: 1, Ready: 1/1, Available: 1/1
Deployment cilium-operator Desired: 1, Ready: 1/1, Available: 1/1
Deployment hubble-relay Desired: 1, Ready: 1/1, Available: 1/1
DaemonSet cilium Desired: 2, Ready: 2/2, Available: 2/2
Containers: cilium Running: 2
hubble-ui Running: 1
cilium-operator Running: 1
hubble-relay Running: 1
Cluster Pods: 4/4 managed by Cilium
Helm chart version: 1.14.5
Image versions cilium quay.io/cilium/cilium:v1.14.5@sha256:d3b287029755b6a47dee01420e2ea469469f1b174a2089c10af7e5e9289ef05b: 2
hubble-ui quay.io/cilium/hubble-ui-backend:v0.12.1@sha256:1f86f3400827a0451e6332262467f894eeb7caf0eb8779bd951e2caa9d027cbe: 1
hubble-ui quay.io/cilium/hubble-ui:v0.12.1@sha256:9e5f81ee747866480ea1ac4630eb6975ff9227f9782b7c93919c081c33f38267: 1
cilium-operator quay.io/cilium/operator-generic:v1.14.5@sha256:303f9076bdc73b3fc32aaedee64a14f6f44c8bb08ee9e3956d443021103ebe7a: 1
hubble-relay quay.io/cilium/hubble-relay:v1.14.5@sha256:dbef89f924a927043d02b40c18e417c1ea0e8f58b44523b80fef7e3652db24d4: 1Hubble observations
If the worker nodes are reachable, you should be able to patch the hubble-ui Service and reach Hubble UI on a NodePort (a high port on a worker node) by patching the Service:
kubectl -n kube-system patch svc/hubble-ui -p '{"spec": {"type": "NodePort"}}'Not much happenings in there though:
Or, if you (as me) have compiled the Hubble CLI:
kubectl port-forward -n kube-system svc/hubble-relay 4245:80 &
[1] 38838
[root@beast /var/tmp/k8sbsd]# Forwarding from 127.0.0.1:4245 -> 4245
Forwarding from [::1]:4245 -> 4245
hubble observe -n kube-system
Handling connection for 4245
Jan 02 07:38:09.681: 127.0.0.1:59698 (world) <> kube-system/coredns-7fd867d5c-t8h8m (ID:46775) pre-xlate-rev TRACED (TCP)
Jan 02 07:38:10.680: 127.0.0.1:59700 (world) <> kube-system/coredns-7fd867d5c-t8h8m (ID:46775) pre-xlate-rev TRACED (TCP)
Jan 02 07:38:10.681: 127.0.0.1:8080 (world) <> kube-system/coredns-7fd867d5c-t8h8m (ID:46775) pre-xlate-rev TRACED (TCP)
Jan 02 07:38:11.233: kube-system/hubble-relay-565664bf9f-n5j4v:56128 (ID:9981) -> 192.168.168.21:4244 (host) to-stack FORWARDED (TCP Flags: ACK)
Jan 02 07:38:11.233: kube-system/hubble-relay-565664bf9f-n5j4v:56128 (ID:9981) <- 192.168.168.21:4244 (host) to-endpoint FORWARDED (TCP Flags: ACK)
Jan 02 07:38:11.558: kube-system/hubble-ui-6f48889749-nttn8:40432 (ID:9425) -> kube-system/hubble-relay-565664bf9f-n5j4v:4245 (ID:9981) to-endpoint FORWARDED (TCP Flags: ACK, PSH)
Jan 02 07:38:11.559: kube-system/hubble-ui-6f48889749-nttn8:40432 (ID:9425) <- kube-system/hubble-relay-565664bf9f-n5j4v:4245 (ID:9981) to-endpoint FORWARDED (TCP Flags: ACK, PSH)Or, if you only check at the cilium-agent (but be aware, it will be local to the node running the agent):
kubectl -n kube-system exec ds/cilium -it -- hubble observe -n kube-system
Defaulted container "cilium-agent" out of: cilium-agent, config (init), mount-cgroup (init), apply-sysctl-overwrites (init), mount-bpf-fs (init), clean-cilium-state (init), install-cni-binaries (init)
Jan 02 07:40:55.550: 10.0.1.178:55564 (world) -> kube-system/hubble-ui-6f48889749-nttn8:8081 (ID:9425) to-overlay FORWARDED (TCP Flags: ACK)
Jan 02 07:40:55.556: 10.0.1.178:55564 (world) -> kube-system/hubble-ui-6f48889749-nttn8:8081 (ID:9425) to-overlay FORWARDED (TCP Flags: ACK)
Jan 02 07:40:55.654: 127.0.0.1:8080 (world) <> kube-system/coredns-7fd867d5c-hsmk9 (ID:46775) pre-xlate-rev TRACED (TCP)
Jan 02 07:40:55.654: 127.0.0.1:56818 (world) <> kube-system/coredns-7fd867d5c-hsmk9 (ID:46775) pre-xlate-rev TRACED (TCP)
Jan 02 07:40:56.654: 127.0.0.1:8080 (world) <> kube-system/coredns-7fd867d5c-hsmk9 (ID:46775) pre-xlate-rev TRACED (TCP)Demo applications
Try the https://docs.cilium.io/en/stable/gettingstarted/demo/#starwars-demo
You can’t tell by the output if it was taken from the documentation or live:
kubectl create -f https://raw.githubusercontent.com/cilium/cilium/1.14.5/examples/minikube/http-sw-app.yaml
service/deathstar created
deployment.apps/deathstar created
pod/tiefighter created
pod/xwing createdBut it was live:
kubectl version -o json
{
"clientVersion": {
"major": "1",
"minor": "29+",
"gitVersion": "v1.29.0-1+d15af86e9e661f",
"gitCommit": "d15af86e9e661f5031d904ebcc0dfbf2cb3d2117",
"gitTreeState": "clean",
"buildDate": "2023-12-13T20:19:35Z",
"goVersion": "go1.21.5",
"compiler": "gc",
"platform": "freebsd/amd64"
},
"kustomizeVersion": "v5.0.4-0.20230601165947-6ce0bf390ce3",
"serverVersion": {
"major": "1",
"minor": "29+",
"gitVersion": "v1.29.0-1+d15af86e9e661f",
"gitCommit": "d15af86e9e661f5031d904ebcc0dfbf2cb3d2117",
"gitTreeState": "clean",
"buildDate": "2023-12-13T20:20:25Z",
"goVersion": "go1.21.5",
"compiler": "gc",
"platform": "freebsd/amd64"
}
}Restrictions and limitations
Basically anything that requires a dynamic admission controller would be expected to fail, as the kube-apiserver does not really know how to reach a ClusterIP. I’ve written a little about it before, but one way to solve it is by exposing the ClusterIP and then help the apiserver with some advanced routing (BGP). Another way is to patch the mutating and validating admission controllers so that the services are externally reachable.
As I mentioned in the video, this is just at an experimental stage and far from being official acknowledged and the conformance testing complains on a couple of tests — but that doesn’t stop it from being useful (and fun!). Just be aware of the limitations.
In a planned third part I’ll cover the routing so that admission controllers expects to work as well..
YouTube appearance
I’m not that OBS savy (yet), and while the demo went (relatively) smoothly it was my second attempt — during the first day of 2024. My first attempt happened on the very last day of 2023 and I felt satisfied when I pressed stop as I had to go through some troubleshooting which I resolved. Then, looking though the result — everything was LTRIM() and missing the first character in every line from the terminal, ha ha. I wanted to do my video in 2023, but I had better things to do on that very day.
My first video was made in three attempts due to bad resolution in the first attempt, frozen picture on the second. My third video might end up well on the first attempt…
