github
/
k3s
mirror of https://github.com/k3s-io/k3s
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
k3s/install.sh

423 lines
12 KiB
Bash
Executable File
Raw Blame History

#!/bin/sh
set -e
# Usage:
# curl ... | ENV_VAR=... sh -
# or
# ENV_VAR=... ./install.sh
#
# Example:
# Installing a server without an agent:
# curl ... | INSTALL_K3S_EXEC="--disable-agent" sh -
# Installing an agent to point at a server:
# curl ... | K3S_TOKEN=xxx K3S_URL=https://server-url:6443 sh -
#
# Environment variables:
# - K3S_*
# Environment variables which begin with K3S_ will be preserved for the
# systemd service to use. Setting K3S_URL without explicitly setting
# a systemd exec command will default the command to "agent", and we
# enforce that K3S_TOKEN or K3S_CLUSTER_SECRET is also set.
#
# - INSTALL_K3S_SKIP_DOWNLOAD
# If set to true will not download k3s hash or binary.
#
# - INSTALL_K3S_VERSION
# Version of k3s to download from github. Will attempt to download the
# latest version if not specified.
#
# - INSTALL_K3S_BIN_DIR
# Directory to install k3s binary, links, and uninstall script to, or use
# /usr/local/bin as the default
#
# - INSTALL_K3S_SYSTEMD_DIR
# Directory to install systemd service and environment files to, or use
# /etc/systemd/system as the default
#
# - INSTALL_K3S_EXEC or script arguments
# Command with flags to use for launching k3s in the systemd service, if
# the command is not specified will default to "agent" if K3S_URL is set
# or "server" if not. The final systemd command resolves to a combination
# of EXEC and script args ($@).
#
# The following commands result in the same behavior:
# curl ... | INSTALL_K3S_EXEC="--disable-agent" sh -s -
# curl ... | INSTALL_K3S_EXEC="server --disable-agent" sh -s -
# curl ... | INSTALL_K3S_EXEC="server" sh -s - --disable-agent
# curl ... | sh -s - server --disable-agent
# curl ... | sh -s - --disable-agent
#
# - INSTALL_K3S_NAME
# Name of systemd service to create, will default from the k3s exec command
# if not specified. If specified the name will be prefixed with 'k3s-'.
#
# - INSTALL_K3S_TYPE
# Type of systemd service to create, will default from the k3s exec command
# if not specified.
GITHUB_URL=https://github.com/rancher/k3s/releases
# --- helper functions for logs ---
info()
{
echo "[INFO] " "$@"
}
fatal()
{
echo "[ERROR] " "$@"
exit 1
}
# --- fatal if no systemd ---
verify_systemd() {
if [ ! -d /run/systemd ]; then
fatal "Can not find systemd to use as a process supervisor for k3s"
fi
}
# --- define needed environment variables ---
setup_env() {
# --- use command args if passed or create default ---
case "$1" in
# --- if we only have flags discover if command should be server or agent ---
(-*|"")
if [ -z "${K3S_URL}" ]; then
CMD_K3S=server
else
if [ -z "${K3S_TOKEN}" ] && [ -z "${K3S_CLUSTER_SECRET}" ]; then
fatal "Defaulted k3s exec command to 'agent' because K3S_URL is defined, but K3S_TOKEN or K3S_CLUSTER_SECRET is not defined."
fi
CMD_K3S=agent
fi
CMD_K3S_EXEC="${CMD_K3S} $@"
;;
# --- command is provided ---
(*)
CMD_K3S="$1"
CMD_K3S_EXEC="$@"
;;
esac
CMD_K3S_EXEC=$(trim() { echo $@; } && trim ${CMD_K3S_EXEC})
# --- use systemd name if defined or create default ---
if [ -n "${INSTALL_K3S_NAME}" ]; then
SYSTEMD_NAME=k3s-${INSTALL_K3S_NAME}
else
if [ "${CMD_K3S}" = "server" ]; then
SYSTEMD_NAME=k3s
else
SYSTEMD_NAME=k3s-${CMD_K3S}
fi
fi
SERVICE_K3S=${SYSTEMD_NAME}.service
UNINSTALL_K3S_SH=${SYSTEMD_NAME}-uninstall.sh
# --- use systemd type if defined or create default ---
if [ -n "${INSTALL_K3S_TYPE}" ]; then
SYSTEMD_TYPE="${INSTALL_K3S_TYPE}"
else
if [ "${CMD_K3S}" = "server" ]; then
SYSTEMD_TYPE=notify
else
SYSTEMD_TYPE=exec
fi
fi
# --- use binary install directory if defined or create default ---
if [ -n "${INSTALL_K3S_BIN_DIR}" ]; then
BIN_DIR="${INSTALL_K3S_BIN_DIR}"
else
BIN_DIR="/usr/local/bin"
fi
# --- use systemd directory if defined or create default ---
if [ -n "${INSTALL_K3S_SYSTEMD_DIR}" ]; then
SYSTEMD_DIR="${INSTALL_K3S_SYSTEMD_DIR}"
else
SYSTEMD_DIR="/etc/systemd/system"
fi
# --- use sudo if we are not already root ---
SUDO=sudo
if [ `id -u` = 0 ]; then
SUDO=
fi
}
# --- check if skip download environment variable set ---
can_skip_download() {
if [ "${INSTALL_K3S_SKIP_DOWNLOAD}" != "true" ]; then
return 1
fi
}
# --- verify an executabe k3s binary is installed ---
verify_k3s_is_executable() {
if [ ! -x ${BIN_DIR}/k3s ]; then
fatal "Executable k3s binary not found at ${BIN_DIR}/k3s"
fi
}
# --- set arch and suffix, fatal if architecture not supported ---
setup_verify_arch() {
ARCH=`uname -m`
case $ARCH in
amd64)
ARCH=amd64
SUFFIX=
;;
x86_64)
ARCH=amd64
SUFFIX=
;;
arm64)
ARCH=arm64
SUFFIX=-${ARCH}
;;
aarch64)
ARCH=arm64
SUFFIX=-${ARCH}
;;
arm*)
ARCH=arm
SUFFIX=-${ARCH}hf
;;
*)
fatal "Unsupported architecture $ARCH"
esac
}
# --- fatal if no curl ---
verify_curl() {
if [ -z `which curl || true` ]; then
fatal "Can not find curl for downloading files"
fi
}
# --- create tempory directory and cleanup when done ---
setup_tmp() {
TMP_DIR=`mktemp -d -t k3s-install.XXXXXXXXXX`
TMP_HASH=${TMP_DIR}/k3s.hash
TMP_BIN=${TMP_DIR}/k3s.bin
cleanup() {
code=$?
set +e
trap - EXIT
rm -rf ${TMP_DIR}
exit $code
}
trap cleanup INT EXIT
}
# --- use desired k3s version if defined or find latest ---
get_release_version() {
if [ -n "${INSTALL_K3S_VERSION}" ]; then
VERSION_K3S="${INSTALL_K3S_VERSION}"
else
info "Finding latest release"
VERSION_K3S=`curl -w "%{url_effective}" -I -L -s -S ${GITHUB_URL}/latest -o /dev/null | sed -e 's|.*/||'`
fi
info "Using ${VERSION_K3S} as release"
}
# --- download hash from github url ---
download_hash() {
HASH_URL=${GITHUB_URL}/download/${VERSION_K3S}/sha256sum-${ARCH}.txt
info "Downloading hash ${HASH_URL}"
curl -o ${TMP_HASH} -sfL ${HASH_URL} || fatal "Hash download failed"
HASH_EXPECTED=`grep k3s ${TMP_HASH} | awk '{print $1}'`
}
# --- check hash against installed version ---
installed_hash_matches() {
if [ -x ${BIN_DIR}/k3s ]; then
HASH_INSTALLED=`sha256sum ${BIN_DIR}/k3s | awk '{print $1}'`
if [ "${HASH_EXPECTED}" = "${HASH_INSTALLED}" ]; then
return
fi
fi
return 1
}
# --- download binary from github url ---
download_binary() {
BIN_URL=${GITHUB_URL}/download/${VERSION_K3S}/k3s${SUFFIX}
info "Downloading binary ${BIN_URL}"
curl -o ${TMP_BIN} -sfL ${BIN_URL} || fatal "Binary download failed"
}
# --- verify downloaded binary hash ---
verify_binary() {
info "Verifying binary download"
HASH_BIN=`sha256sum ${TMP_BIN} | awk '{print $1}'`
if [ "${HASH_EXPECTED}" != "${HASH_BIN}" ]; then
fatal "Download sha256 does not match ${HASH_EXPECTED}, got ${HASH_BIN}"
fi
}
# --- setup permissions and move binary to system directory ---
setup_binary() {
chmod 755 ${TMP_BIN}
info "Installing k3s to ${BIN_DIR}/k3s"
$SUDO chown root:root ${TMP_BIN}
$SUDO mv -f ${TMP_BIN} ${BIN_DIR}/k3s
}
# --- download and verify k3s ---
download_and_verify() {
if can_skip_download; then
info "Skipping k3s download and verify"
verify_k3s_is_executable
return
fi
setup_verify_arch
verify_curl
setup_tmp
get_release_version
download_hash
if installed_hash_matches; then
info "Skipping binary downloaded, installed k3s matches hash"
return
fi
download_binary
verify_binary
setup_binary
}
# --- add additional utility links ---
create_symlinks() {
if [ ! -e ${BIN_DIR}/kubectl ]; then
info "Creating ${BIN_DIR}/kubectl symlink to k3s"
$SUDO ln -s k3s ${BIN_DIR}/kubectl
fi
if [ ! -e ${BIN_DIR}/crictl ]; then
info "Creating ${BIN_DIR}/crictl symlink to k3s"
$SUDO ln -s k3s ${BIN_DIR}/crictl
fi
}
# --- create uninstall script ---
create_uninstall() {
info "Creating uninstall script ${BIN_DIR}/${UNINSTALL_K3S_SH}"
$SUDO tee ${BIN_DIR}/${UNINSTALL_K3S_SH} >/dev/null << EOF
#!/bin/sh
set -x
systemctl kill ${SYSTEMD_NAME}
systemctl disable ${SYSTEMD_NAME}
systemctl reset-failed ${SYSTEMD_NAME}
systemctl daemon-reload
rm -f ${SYSTEMD_DIR}/${SERVICE_K3S}
rm -f ${SYSTEMD_DIR}/${SERVICE_K3S}.env
remove_uninstall() {
rm -f ${BIN_DIR}/${UNINSTALL_K3S_SH}
}
trap remove_uninstall EXIT
if ls ${SYSTEMD_DIR}/k3s*.service >/dev/null 2>&1; then
set +x; echo "Additional k3s services installed, skipping uninstall of k3s"; set -x
exit
fi
do_unmount() {
MOUNTS=\`cat /proc/self/mounts | awk '{print \$2}' | grep "^\$1"\`
if [ -n "\${MOUNTS}" ]; then
umount \${MOUNTS}
fi
}
do_unmount '/run/k3s'
do_unmount '/var/lib/rancher/k3s'
nets=\$(ip link show master cni0 | grep cni0 | awk -F': ' '{print \$2}' | sed -e 's|@.*||')
for iface in \$nets; do
ip link delete \$iface;
done
ip link delete cni0
ip link delete flannel.1
if [ -L ${BIN_DIR}/kubectl ]; then
rm -f ${BIN_DIR}/kubectl
fi
if [ -L ${BIN_DIR}/crictl ]; then
rm -f ${BIN_DIR}/crictl
fi
rm -rf /etc/rancher/k3s
rm -rf /var/lib/rancher/k3s
rm -f ${BIN_DIR}/k3s
EOF
$SUDO chmod 755 ${BIN_DIR}/${UNINSTALL_K3S_SH}
$SUDO chown root:root ${BIN_DIR}/${UNINSTALL_K3S_SH}
}
# --- disable current service if loaded --
systemd_disable() {
$SUDO rm -f /etc/systemd/system/${SERVICE_K3S} || true
$SUDO rm -f /etc/systemd/system/${SERVICE_K3S}.env || true
$SUDO systemctl disable ${SYSTEMD_NAME} >/dev/null 2>&1 || true
}
# --- capture current env and create file containing k3s_ variables ---
create_env_file() {
info "systemd: Creating environment file ${SYSTEMD_DIR}/${SERVICE_K3S}.env"
UMASK=`umask`
umask 0377
env | grep '^K3S_' | $SUDO tee ${SYSTEMD_DIR}/${SERVICE_K3S}.env >/dev/null
umask $UMASK
}
# --- write service file ---
create_service_file() {
info "systemd: Creating service file ${SYSTEMD_DIR}/${SERVICE_K3S}"
$SUDO tee ${SYSTEMD_DIR}/${SERVICE_K3S} >/dev/null << EOF
[Unit]
Description=Lightweight Kubernetes
Documentation=https://k3s.io
After=network.target
[Service]
Type=${SYSTEMD_TYPE}
EnvironmentFile=${SYSTEMD_DIR}/${SERVICE_K3S}.env
ExecStartPre=-/sbin/modprobe br_netfilter
ExecStartPre=-/sbin/modprobe overlay
ExecStart=${BIN_DIR}/k3s ${CMD_K3S_EXEC}
KillMode=process
Delegate=yes
LimitNOFILE=infinity
LimitNPROC=infinity
LimitCORE=infinity
TasksMax=infinity
[Install]
WantedBy=multi-user.target
EOF
}
# --- enable and start systemd service ---
systemd_enable_and_start() {
info "systemd: Enabling ${SYSTEMD_NAME} unit"
$SUDO systemctl enable ${SYSTEMD_DIR}/${SERVICE_K3S} >/dev/null
$SUDO systemctl daemon-reload >/dev/null
info "systemd: Starting ${SYSTEMD_NAME}"
$SUDO systemctl restart ${SYSTEMD_NAME}
}
# --- run the install process --
{
verify_systemd
setup_env ${INSTALL_K3S_EXEC} $@
download_and_verify
create_symlinks
create_uninstall
systemd_disable
create_env_file
create_service_file
systemd_enable_and_start
}
Reference in New Issue View Git Blame Copy Permalink