#!/bin/sh set -e # Usage: # curl ... | ENV_VAR=... sh - # or # ENV_VAR=... ./install.sh # # Example: # Installing a server without traefik: # curl ... | INSTALL_K3S_EXEC="--no-deploy=traefik" 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_SYMLINK # If set to 'skip' will not create symlinks, 'force' will overwrite, # default will symlink if command does not exist in path. # # - INSTALL_K3S_SKIP_ENABLE # If set to true will not enable or start k3s service. # # - INSTALL_K3S_SKIP_START # If set to true will not start k3s service. # # - INSTALL_K3S_VERSION # Version of k3s to download from github. Will attempt to download the # latest version if not specified. # # - INSTALL_K3S_COMMIT # Commit of k3s to download from temporary cloud storage. # * (for developer & QA use) # # - INSTALL_K3S_BIN_DIR # Directory to install k3s binary, links, and uninstall script to, or use # /usr/local/bin as the default # # - INSTALL_K3S_BIN_DIR_READ_ONLY # If set to true will not write files to INSTALL_K3S_BIN_DIR, forces # setting INSTALL_K3S_SKIP_DOWNLOAD=true # # - 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 ($@). # # The following commands result in the same behavior: # curl ... | INSTALL_K3S_EXEC="--no-deploy=traefik" sh -s - # curl ... | INSTALL_K3S_EXEC="server --no-deploy=traefik" sh -s - # curl ... | INSTALL_K3S_EXEC="server" sh -s - --no-deploy=traefik # curl ... | sh -s - server --no-deploy=traefik # curl ... | sh -s - --no-deploy=traefik # # - INSTALL_K3S_NAME # Name of systemd service to create, will default from the k3s exec command # if not specified. If specified the name will be prefixed with 'k3s-'. # # - INSTALL_K3S_TYPE # Type of systemd service to create, will default from the k3s exec command # if not specified. GITHUB_URL=https://github.com/rancher/k3s/releases STORAGE_URL=https://storage.googleapis.com/k3s-ci-builds DOWNLOADER= # --- helper functions for logs --- info() { echo '[INFO] ' "$@" } fatal() { echo '[ERROR] ' "$@" >&2 exit 1 } # --- fatal if no systemd or openrc --- verify_system() { if [ -x /sbin/openrc-run ]; then HAS_OPENRC=true return fi if [ -d /run/systemd ]; then HAS_SYSTEMD=true return fi fatal 'Can not find systemd or openrc to use as a process supervisor for k3s' } # --- add quotes to command arguments --- quote() { for arg in "$@"; do printf '%s\n' "$arg" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/'/" done } # --- add indentation and trailing slash to quoted args --- quote_indent() { printf ' \\\n' for arg in "$@"; do printf '\t%s \\\n' "$(quote "$arg")" done } # --- escape most punctuation characters, except quotes, forward slash, and space --- escape() { printf '%s' "$@" | sed -e 's/\([][!#$%&()*;<=>?\_`{|}]\)/\\\1/g;' } # --- escape double quotes --- escape_dq() { printf '%s' "$@" | sed -e 's/"/\\"/g' } # --- 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 ;; # --- command is provided --- (*) CMD_K3S=$1 shift ;; esac CMD_K3S_EXEC="${CMD_K3S}$(quote_indent "$@")" # --- use systemd name if defined or create default --- if [ -n "${INSTALL_K3S_NAME}" ]; then SYSTEM_NAME=k3s-${INSTALL_K3S_NAME} else if [ "${CMD_K3S}" = server ]; then SYSTEM_NAME=k3s else SYSTEM_NAME=k3s-${CMD_K3S} fi fi # --- check for invalid characters in system name --- valid_chars=$(printf '%s' "${SYSTEM_NAME}" | sed -e 's/[][!#$%&()*;<=>?\_`{|}/[:space:]]/^/g;' ) if [ "${SYSTEM_NAME}" != "${valid_chars}" ]; then invalid_chars=$(printf '%s' "${valid_chars}" | sed -e 's/[^^]/ /g') fatal "Invalid characters for system name: ${SYSTEM_NAME} ${invalid_chars}" fi # --- use sudo if we are not already root --- SUDO=sudo if [ $(id -u) -eq 0 ]; then SUDO= fi # --- use systemd type if defined or create default --- if [ -n "${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 # --- set related files from system name --- SERVICE_K3S=${SYSTEM_NAME}.service UNINSTALL_K3S_SH=${UNINSTALL_K3S_SH:-${BIN_DIR}/${SYSTEM_NAME}-uninstall.sh} KILLALL_K3S_SH=${KILLALL_K3S_SH:-${BIN_DIR}/k3s-killall.sh} # --- use service or environment location depending on systemd/openrc --- if [ "${HAS_SYSTEMD}" = true ]; then FILE_K3S_SERVICE=${SYSTEMD_DIR}/${SERVICE_K3S} FILE_K3S_ENV=${SYSTEMD_DIR}/${SERVICE_K3S}.env elif [ "${HAS_OPENRC}" = true ]; then $SUDO mkdir -p /etc/rancher/k3s FILE_K3S_SERVICE=/etc/init.d/${SYSTEM_NAME} FILE_K3S_ENV=/etc/rancher/k3s/${SYSTEM_NAME}.env fi # --- get hash of config & exec for currently installed k3s --- PRE_INSTALL_HASHES=$(get_installed_hashes) # --- if bin directory is read only skip download --- if [ "${INSTALL_K3S_BIN_DIR_READ_ONLY}" = true ]; then INSTALL_K3S_SKIP_DOWNLOAD=true fi } # --- check if skip download environment variable set --- can_skip_download() { if [ "${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 ${BIN_DIR}/k3s" fi } # --- set arch and suffix, fatal if architecture not supported --- setup_verify_arch() { if [ -z "$ARCH" ]; then ARCH=$(uname -m) fi 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 $ARCH" esac } # --- verify existence of network downloader executable --- verify_downloader() { # Return failure if it doesn't exist or is no executable [ -x "$(which $1)" ] || return 1 # Set verified executable as our downloader program and return success DOWNLOADER=$1 return 0 } # --- verify existence of semanage when SELinux is enabled --- verify_semanage() { if [ -x "$(which getenforce)" ]; then if [ "Disabled" != $(getenforce) ] && [ ! -x "$(which semanage)" ]; then fatal 'SELinux is enabled but semanage is not found' fi 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_COMMIT}" ]; then VERSION_K3S="commit ${INSTALL_K3S_COMMIT}" elif [ -n "${INSTALL_K3S_VERSION}" ]; then VERSION_K3S=${INSTALL_K3S_VERSION} else info "Finding latest release" case $DOWNLOADER in curl) VERSION_K3S=$(curl -w '%{url_effective}' -I -L -s -S ${GITHUB_URL}/latest -o /dev/null | sed -e 's|.*/||') ;; wget) VERSION_K3S=$(wget -SqO /dev/null ${GITHUB_URL}/latest 2>&1 | grep Location | sed -e 's|.*/||') ;; *) fatal "Incorrect downloader executable '$DOWNLOADER'" ;; esac fi info "Using ${VERSION_K3S} as release" } # --- download from github url --- download() { [ $# -eq 2 ] || fatal 'download needs exactly 2 arguments' case $DOWNLOADER in curl) curl -o $1 -sfL $2 ;; wget) wget -qO $1 $2 ;; *) fatal "Incorrect executable '$DOWNLOADER'" ;; esac # Abort if download command failed [ $? -eq 0 ] || fatal 'Download failed' } # --- download hash from github url --- download_hash() { if [ -n "${INSTALL_K3S_COMMIT}" ]; then HASH_URL=${STORAGE_URL}/k3s${SUFFIX}-${INSTALL_K3S_COMMIT}.sha256sum else HASH_URL=${GITHUB_URL}/download/${VERSION_K3S}/sha256sum-${ARCH}.txt fi info "Downloading hash ${HASH_URL}" download ${TMP_HASH} ${HASH_URL} HASH_EXPECTED=$(grep " k3s${SUFFIX}$" ${TMP_HASH}) HASH_EXPECTED=${HASH_EXPECTED%%[[:blank:]]*} } # --- check hash against installed version --- installed_hash_matches() { if [ -x ${BIN_DIR}/k3s ]; then HASH_INSTALLED=$(sha256sum ${BIN_DIR}/k3s) HASH_INSTALLED=${HASH_INSTALLED%%[[:blank:]]*} if [ "${HASH_EXPECTED}" = "${HASH_INSTALLED}" ]; then return fi fi return 1 } # --- download binary from github url --- download_binary() { if [ -n "${INSTALL_K3S_COMMIT}" ]; then BIN_URL=${STORAGE_URL}/k3s${SUFFIX}-${INSTALL_K3S_COMMIT} else BIN_URL=${GITHUB_URL}/download/${VERSION_K3S}/k3s${SUFFIX} fi info "Downloading binary ${BIN_URL}" download ${TMP_BIN} ${BIN_URL} } # --- verify downloaded binary hash --- verify_binary() { info "Verifying binary download" HASH_BIN=$(sha256sum ${TMP_BIN}) HASH_BIN=${HASH_BIN%%[[:blank:]]*} 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 if command -v getenforce >/dev/null 2>&1; then if [ "Disabled" != $(getenforce) ]; then info 'SELinux is enabled, setting permissions' if ! $SUDO semanage fcontext -l | grep "${BIN_DIR}/k3s" > /dev/null 2>&1; then $SUDO semanage fcontext -a -t bin_t "${BIN_DIR}/k3s" fi $SUDO restorecon -v ${BIN_DIR}/k3s > /dev/null fi fi } # --- download and verify k3s --- download_and_verify() { if can_skip_download; then info 'Skipping k3s download and verify' verify_k3s_is_executable return fi setup_verify_arch verify_downloader curl || verify_downloader wget || fatal 'Can not find curl or wget for downloading files' verify_semanage setup_tmp get_release_version download_hash if installed_hash_matches; then info 'Skipping binary downloaded, installed k3s matches hash' return fi download_binary verify_binary setup_binary } # --- add additional utility links --- create_symlinks() { [ "${INSTALL_K3S_BIN_DIR_READ_ONLY}" = true ] && return [ "${INSTALL_K3S_SYMLINK}" = skip ] && return for cmd in kubectl crictl ctr; do if [ ! -e ${BIN_DIR}/${cmd} ] || [ "${INSTALL_K3S_SYMLINK}" = force ]; then which_cmd=$(which ${cmd} 2>/dev/null || true) if [ -z "${which_cmd}" ] || [ "${INSTALL_K3S_SYMLINK}" = force ]; then info "Creating ${BIN_DIR}/${cmd} symlink to k3s" $SUDO ln -sf k3s ${BIN_DIR}/${cmd} else info "Skipping ${BIN_DIR}/${cmd} symlink to k3s, command exists in PATH at ${which_cmd}" fi else info "Skipping ${BIN_DIR}/${cmd} symlink to k3s, already exists" fi done } # --- create killall script --- create_killall() { [ "${INSTALL_K3S_BIN_DIR_READ_ONLY}" = true ] && return info "Creating killall script ${KILLALL_K3S_SH}" $SUDO tee ${KILLALL_K3S_SH} >/dev/null << \EOF #!/bin/sh [ $(id -u) -eq 0 ] || exec sudo $0 $@ for bin in /var/lib/rancher/k3s/data/**/bin/; do [ -d $bin ] && export PATH=$PATH:$bin:$bin/aux done set -x for service in /etc/systemd/system/k3s*.service; do [ -s $service ] && systemctl stop $(basename $service) done for service in /etc/init.d/k3s*; do [ -x $service ] && $service stop done pschildren() { ps -e -o ppid= -o pid= | \ sed -e 's/^\s*//g; s/\s\s*/\t/g;' | \ grep -w "^$1" | \ cut -f2 } pstree() { for pid in $@; do echo $pid for child in $(pschildren $pid); do pstree $child done done } killtree() { kill -9 $( { set +x; } 2>/dev/null; pstree $@; set -x; ) 2>/dev/null } getshims() { ps -e -o pid= -o args= | sed -e 's/^ *//; s/\s\s*/\t/;' | grep -w 'k3s/data/[^/]*/bin/containerd-shim' | cut -f1 } killtree $({ set +x; } 2>/dev/null; getshims; set -x) do_unmount() { { set +x; } 2>/dev/null MOUNTS= while read ignore mount ignore; do MOUNTS="$mount\n$MOUNTS" done /dev/null | grep 'master cni0' | while read ignore iface ignore; do iface=${iface%%@*} [ -z "$iface" ] || ip link delete $iface done ip link delete cni0 ip link delete flannel.1 rm -rf /var/lib/cni/ iptables-save | grep -v KUBE- | grep -v CNI- | iptables-restore EOF $SUDO chmod 755 ${KILLALL_K3S_SH} $SUDO chown root:root ${KILLALL_K3S_SH} } # --- create uninstall script --- create_uninstall() { [ "${INSTALL_K3S_BIN_DIR_READ_ONLY}" = true ] && return info "Creating uninstall script ${UNINSTALL_K3S_SH}" $SUDO tee ${UNINSTALL_K3S_SH} >/dev/null << EOF #!/bin/sh set -x [ \$(id -u) -eq 0 ] || exec sudo \$0 \$@ ${KILLALL_K3S_SH} if which systemctl; then systemctl disable ${SYSTEM_NAME} systemctl reset-failed ${SYSTEM_NAME} systemctl daemon-reload fi if which rc-update; then rc-update delete ${SYSTEM_NAME} default fi rm -f ${FILE_K3S_SERVICE} rm -f ${FILE_K3S_ENV} remove_uninstall() { rm -f ${UNINSTALL_K3S_SH} } trap remove_uninstall EXIT if (ls ${SYSTEMD_DIR}/k3s*.service || ls /etc/init.d/k3s*) >/dev/null 2>&1; then set +x; echo 'Additional k3s services installed, skipping uninstall of k3s'; set -x exit fi for cmd in kubectl crictl ctr; do if [ -L ${BIN_DIR}/\$cmd ]; then rm -f ${BIN_DIR}/\$cmd fi done rm -rf /etc/rancher/k3s rm -rf /var/lib/rancher/k3s rm -rf /var/lib/kubelet rm -f ${BIN_DIR}/k3s rm -f ${KILLALL_K3S_SH} EOF $SUDO chmod 755 ${UNINSTALL_K3S_SH} $SUDO chown root:root ${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 ${SYSTEM_NAME} >/dev/null 2>&1 || true } # --- capture current env and create file containing k3s_ variables --- create_env_file() { info "env: Creating environment file ${FILE_K3S_ENV}" UMASK=$(umask) umask 0377 env | grep '^K3S_' | $SUDO tee ${FILE_K3S_ENV} >/dev/null env | egrep -i '^(NO|HTTP|HTTPS)_PROXY' | $SUDO tee -a ${FILE_K3S_ENV} >/dev/null umask $UMASK } # --- write systemd service file --- create_systemd_service_file() { info "systemd: Creating service file ${FILE_K3S_SERVICE}" $SUDO tee ${FILE_K3S_SERVICE} >/dev/null << EOF [Unit] Description=Lightweight Kubernetes Documentation=https://k3s.io Wants=network-online.target [Install] WantedBy=multi-user.target [Service] Type=${SYSTEMD_TYPE} EnvironmentFile=${FILE_K3S_ENV} KillMode=process Delegate=yes LimitNOFILE=infinity LimitNPROC=infinity LimitCORE=infinity TasksMax=infinity TimeoutStartSec=0 Restart=always RestartSec=5s ExecStartPre=-/sbin/modprobe br_netfilter ExecStartPre=-/sbin/modprobe overlay ExecStart=${BIN_DIR}/k3s \\ ${CMD_K3S_EXEC} EOF } # --- write openrc service file --- create_openrc_service_file() { LOG_FILE=/var/log/${SYSTEM_NAME}.log info "openrc: Creating service file ${FILE_K3S_SERVICE}" $SUDO tee ${FILE_K3S_SERVICE} >/dev/null << EOF #!/sbin/openrc-run depend() { after network-online want cgroups } start_pre() { rm -f /tmp/k3s.* } supervisor=supervise-daemon name=${SYSTEM_NAME} command="${BIN_DIR}/k3s" command_args="$(escape_dq "${CMD_K3S_EXEC}") >>${LOG_FILE} 2>&1" output_log=${LOG_FILE} error_log=${LOG_FILE} pidfile="/var/run/${SYSTEM_NAME}.pid" respawn_delay=5 set -o allexport if [ -f /etc/environment ]; then source /etc/environment; fi if [ -f ${FILE_K3S_ENV} ]; then source ${FILE_K3S_ENV}; fi set +o allexport EOF $SUDO chmod 0755 ${FILE_K3S_SERVICE} $SUDO tee /etc/logrotate.d/${SYSTEM_NAME} >/dev/null << EOF ${LOG_FILE} { missingok notifempty copytruncate } EOF } # --- write systemd or openrc service file --- create_service_file() { [ "${HAS_SYSTEMD}" = true ] && create_systemd_service_file [ "${HAS_OPENRC}" = true ] && create_openrc_service_file return 0 } # --- get hashes of the current k3s bin and service files get_installed_hashes() { $SUDO sha256sum ${BIN_DIR}/k3s ${FILE_K3S_SERVICE} ${FILE_K3S_ENV} 2>&1 || true } # --- enable and start systemd service --- systemd_enable() { info "systemd: Enabling ${SYSTEM_NAME} unit" $SUDO systemctl enable ${FILE_K3S_SERVICE} >/dev/null $SUDO systemctl daemon-reload >/dev/null } systemd_start() { info "systemd: Starting ${SYSTEM_NAME}" $SUDO systemctl restart ${SYSTEM_NAME} } # --- enable and start openrc service --- openrc_enable() { info "openrc: Enabling ${SYSTEM_NAME} service for default runlevel" $SUDO rc-update add ${SYSTEM_NAME} default >/dev/null } openrc_start() { info "openrc: Starting ${SYSTEM_NAME}" $SUDO ${FILE_K3S_SERVICE} restart } # --- startup systemd or openrc service --- service_enable_and_start() { [ "${INSTALL_K3S_SKIP_ENABLE}" = true ] && return [ "${HAS_SYSTEMD}" = true ] && systemd_enable [ "${HAS_OPENRC}" = true ] && openrc_enable [ "${INSTALL_K3S_SKIP_START}" = true ] && return POST_INSTALL_HASHES=$(get_installed_hashes) if [ "${PRE_INSTALL_HASHES}" = "${POST_INSTALL_HASHES}" ]; then info 'No change detected so skipping service start' return fi [ "${HAS_SYSTEMD}" = true ] && systemd_start [ "${HAS_OPENRC}" = true ] && openrc_start return 0 } # --- re-evaluate args to include env command --- eval set -- $(escape "${INSTALL_K3S_EXEC}") $(quote "$@") # --- run the install process -- { verify_system setup_env "$@" download_and_verify create_symlinks create_killall create_uninstall systemd_disable create_env_file create_service_file service_enable_and_start }