一、延长k8s证书时间
查看 apiserver 证书有效时间：默认是一年的有效期
[root@xuegod63 ~]#
openssl x509 -in /etc/kubernetes/pki/apiserver.crt -noout -text |grep Not
延长证书过期时间
1.把 update-kubeadm-cert.sh 文件上传到 xuegod63 节点
vim update-kubeadm-cert.sh
#!/bin/bash
set -o errexit
set -o pipefail
# set -o xtrace
log::err() {
printf "[$(date +'%Y-%m-%dT%H:%M:%S.%N%z')]: \033[31mERROR: \033[0m$@\n"
}
log::info() {
printf "[$(date +'%Y-%m-%dT%H:%M:%S.%N%z')]: \033[32mINFO: \033[0m$@\n"
}
log::warning() {
printf "[$(date +'%Y-%m-%dT%H:%M:%S.%N%z')]: \033[33mWARNING: \033[0m$@\n"
}
check_file() {
if [[ ! -r ${1} ]]; then
log::err "can not find ${1}"
exit 1
fi
}
# get x509v3 subject alternative name from the old certificate
cert::get_subject_alt_name() {
local cert=${1}.crt
check_file "${cert}"
local alt_name=$(openssl x509 -text -noout -in ${cert} | grep -A1 'Alternative' | tail -n1 | sed 's/[[:space:]]*Address//g')
printf "${alt_name}\n"
}
# get subject from the old certificate
cert::get_subj() {
local cert=${1}.crt
check_file "${cert}"
local subj=$(openssl x509 -text -noout -in ${cert} | grep "Subject:" | sed 's/Subject:/\//g;s/\,/\//;s/[[:space:]]//g')
printf "${subj}\n"
}
cert::backup_file() {
local file=${1}
if [[ ! -e ${file}.old-$(date +%Y%m%d) ]]; then
cp -rp ${file} ${file}.old-$(date +%Y%m%d)
log::info "backup ${file} to ${file}.old-$(date +%Y%m%d)"
else
log::warning "does not backup, ${file}.old-$(date +%Y%m%d) already exists"
fi
}
# generate certificate whit client, server or peer
# Args:
# $1 (the name of certificate)
# $2 (the type of certificate, must be one of client, server, peer)
# $3 (the subject of certificates)
# $4 (the validity of certificates) (days)
# $5 (the x509v3 subject alternative name of certificate when the type of certificate is server or peer)
cert::gen_cert() {
local cert_name=${1}
local cert_type=${2}
local subj=${3}
local cert_days=${4}
local alt_name=${5}
local cert=${cert_name}.crt
local key=${cert_name}.key
local csr=${cert_name}.csr
local csr_conf="distinguished_name = dn\n[dn]\n[v3_ext]\nkeyUsage = critical, digitalSignature, keyEncipherment\n"
check_file "${key}"
check_file "${cert}"
# backup certificate when certificate not in ${kubeconf_arr[@]}
# kubeconf_arr=("controller-manager.crt" "scheduler.crt" "admin.crt" "kubelet.crt")
# if [[ ! "${kubeconf_arr[@]}" =~ "${cert##*/}" ]]; then
# cert::backup_file "${cert}"
# fi
case "${cert_type}" in
client)
openssl req -new -key ${key} -subj "${subj}" -reqexts v3_ext \
-config <(printf "${csr_conf} extendedKeyUsage = clientAuth\n") -out ${csr}
openssl x509 -in ${csr} -req -CA ${CA_CERT} -CAkey ${CA_KEY} -CAcreateserial -extensions v3_ext \
-extfile <(printf "${csr_conf} extendedKeyUsage = clientAuth\n") -days ${cert_days} -out ${cert}
log::info "generated ${cert}"
;;
server)
openssl req -new -key ${key} -subj "${subj}" -reqexts v3_ext \
-config <(printf "${csr_conf} extendedKeyUsage = serverAuth\nsubjectAltName = ${alt_name}\n") -out ${csr}
openssl x509 -in ${csr} -req -CA ${CA_CERT} -CAkey ${CA_KEY} -CAcreateserial -extensions v3_ext \
-extfile <(printf "${csr_conf} extendedKeyUsage = serverAuth\nsubjectAltName = ${alt_name}\n") -days ${cert_days} -out ${cert}
log::info "generated ${cert}"
;;
peer)
openssl req -new -key ${key} -subj "${subj}" -reqexts v3_ext \
-config <(printf "${csr_conf} extendedKeyUsage = serverAuth, clientAuth\nsubjectAltName = ${alt_name}\n") -out ${csr}
openssl x509 -in ${csr} -req -CA ${CA_CERT} -CAkey ${CA_KEY} -CAcreateserial -extensions v3_ext \
-extfile <(printf "${csr_conf} extendedKeyUsage = serverAuth, clientAuth\nsubjectAltName = ${alt_name}\n") -days ${cert_days} -out ${cert}
log::info "generated ${cert}"
;;
*)
log::err "unknow, unsupported etcd certs type: ${cert_type}, supported type: client, server, peer"
exit 1
esac
rm -f ${csr}
}
cert::update_kubeconf() {
local cert_name=${1}
local kubeconf_file=${cert_name}.conf
local cert=${cert_name}.crt
local key=${cert_name}.key
# generate certificate
check_file ${kubeconf_file}
# get the key from the old kubeconf
grep "client-key-data" ${kubeconf_file} | awk {'print$2'} | base64 -d > ${key}
# get the old certificate from the old kubeconf
grep "client-certificate-data" ${kubeconf_file} | awk {'print$2'} | base64 -d > ${cert}
# get subject from the old certificate
local subj=$(cert::get_subj ${cert_name})
cert::gen_cert "${cert_name}" "client" "${subj}" "${CAER_DAYS}"
# get certificate base64 code
local cert_base64=$(base64 -w 0 ${cert})
# backup kubeconf
# cert::backup_file "${kubeconf_file}"
# set certificate base64 code to kubeconf
sed -i 's/client-certificate-data:.*/client-certificate-data: '${cert_base64}'/g' ${kubeconf_file}
log::info "generated new ${kubeconf_file}"
rm -f ${cert}
rm -f ${key}
# set config for kubectl
if [[ ${cert_name##*/} == "admin" ]]; then
mkdir -p ~/.kube
cp -fp ${kubeconf_file} ~/.kube/config
log::info "copy the admin.conf to ~/.kube/config for kubectl"
fi
}
cert::update_etcd_cert() {
PKI_PATH=${KUBE_PATH}/pki/etcd
CA_CERT=${PKI_PATH}/ca.crt
CA_KEY=${PKI_PATH}/ca.key
check_file "${CA_CERT}"
check_file "${CA_KEY}"
# generate etcd server certificate
# /etc/kubernetes/pki/etcd/server
CART_NAME=${PKI_PATH}/server
subject_alt_name=$(cert::get_subject_alt_name ${CART_NAME})
cert::gen_cert "${CART_NAME}" "peer" "/CN=etcd-server" "${CAER_DAYS}" "${subject_alt_name}"
# generate etcd peer certificate
# /etc/kubernetes/pki/etcd/peer
CART_NAME=${PKI_PATH}/peer
subject_alt_name=$(cert::get_subject_alt_name ${CART_NAME})
cert::gen_cert "${CART_NAME}" "peer" "/CN=etcd-peer" "${CAER_DAYS}" "${subject_alt_name}"
# generate etcd healthcheck-client certificate
# /etc/kubernetes/pki/etcd/healthcheck-client
CART_NAME=${PKI_PATH}/healthcheck-client
cert::gen_cert "${CART_NAME}" "client" "/O=system:masters/CN=kube-etcd-healthcheck-client" "${CAER_DAYS}"
# generate apiserver-etcd-client certificate
# /etc/kubernetes/pki/apiserver-etcd-client
check_file "${CA_CERT}"
check_file "${CA_KEY}"
PKI_PATH=${KUBE_PATH}/pki
CART_NAME=${PKI_PATH}/apiserver-etcd-client
cert::gen_cert "${CART_NAME}" "client" "/O=system:masters/CN=kube-apiserver-etcd-client" "${CAER_DAYS}"
# restart etcd
docker ps | awk '/k8s_etcd/{print$1}' | xargs -r -I '{}' docker restart {} || true
log::info "restarted etcd"
}
cert::update_master_cert() {
PKI_PATH=${KUBE_PATH}/pki
CA_CERT=${PKI_PATH}/ca.crt
CA_KEY=${PKI_PATH}/ca.key
check_file "${CA_CERT}"
check_file "${CA_KEY}"
# generate apiserver server certificate
# /etc/kubernetes/pki/apiserver
CART_NAME=${PKI_PATH}/apiserver
subject_alt_name=$(cert::get_subject_alt_name ${CART_NAME})
cert::gen_cert "${CART_NAME}" "server" "/CN=kube-apiserver" "${CAER_DAYS}" "${subject_alt_name}"
# generate apiserver-kubelet-client certificate
# /etc/kubernetes/pki/apiserver-kubelet-client
CART_NAME=${PKI_PATH}/apiserver-kubelet-client
cert::gen_cert "${CART_NAME}" "client" "/O=system:masters/CN=kube-apiserver-kubelet-client" "${CAER_DAYS}"
# generate kubeconf for controller-manager,scheduler,kubectl and kubelet
# /etc/kubernetes/controller-manager,scheduler,admin,kubelet.conf
cert::update_kubeconf "${KUBE_PATH}/controller-manager"
cert::update_kubeconf "${KUBE_PATH}/scheduler"
cert::update_kubeconf "${KUBE_PATH}/admin"
# check kubelet.conf
# https://github.com/kubernetes/kubeadm/issues/1753
set +e
grep kubelet-client-current.pem /etc/kubernetes/kubelet.conf > /dev/null 2>&1
kubelet_cert_auto_update=$?
set -e
if [[ "$kubelet_cert_auto_update" == "0" ]]; then
log::warning "does not need to update kubelet.conf"
else
cert::update_kubeconf "${KUBE_PATH}/kubelet"
fi
# generate front-proxy-client certificate
# use front-proxy-client ca
CA_CERT=${PKI_PATH}/front-proxy-ca.crt
CA_KEY=${PKI_PATH}/front-proxy-ca.key
check_file "${CA_CERT}"
check_file "${CA_KEY}"
CART_NAME=${PKI_PATH}/front-proxy-client
cert::gen_cert "${CART_NAME}" "client" "/CN=front-proxy-client" "${CAER_DAYS}"
# restart apiserve, controller-manager, scheduler and kubelet
docker ps | awk '/k8s_kube-apiserver/{print$1}' | xargs -r -I '{}' docker restart {} || true
log::info "restarted kube-apiserver"
docker ps | awk '/k8s_kube-controller-manager/{print$1}' | xargs -r -I '{}' docker restart {} || true
log::info "restarted kube-controller-manager"
docker ps | awk '/k8s_kube-scheduler/{print$1}' | xargs -r -I '{}' docker restart {} || true
log::info "restarted kube-scheduler"
systemctl restart kubelet
log::info "restarted kubelet"
}
main() {
local node_tpye=$1
KUBE_PATH=/etc/kubernetes
CAER_DAYS=36500
# backup $KUBE_PATH to $KUBE_PATH.old-$(date +%Y%m%d)
cert::backup_file "${KUBE_PATH}"
case ${node_tpye} in
etcd)
# update etcd certificates
cert::update_etcd_cert
;;
master)
# update master certificates and kubeconf
cert::update_master_cert
;;
all)
# update etcd certificates
cert::update_etcd_cert
# update master certificates and kubeconf
cert::update_master_cert
;;
*)
log::err "unknow, unsupported certs type: ${cert_type}, supported type: all, etcd, master"
printf "Documentation: https://github.com/yuyicai/update-kube-cert
example:
'\033[32m./update-kubeadm-cert.sh all\033[0m' update all etcd certificates, master certificates and kubeconf
/etc/kubernetes
├── admin.conf
├── controller-manager.conf
├── scheduler.conf
├── kubelet.conf
└── pki
├── apiserver.crt
├── apiserver-etcd-client.crt
├── apiserver-kubelet-client.crt
├── front-proxy-client.crt
└── etcd
├── healthcheck-client.crt
├── peer.crt
└── server.crt
'\033[32m./update-kubeadm-cert.sh etcd\033[0m' update only etcd certificates
/etc/kubernetes
└── pki
├── apiserver-etcd-client.crt
└── etcd
├── healthcheck-client.crt
├── peer.crt
└── server.crt
'\033[32m./update-kubeadm-cert.sh master\033[0m' update only master certificates and kubeconf
/etc/kubernetes
├── admin.conf
├── controller-manager.conf
├── scheduler.conf
├── kubelet.conf
└── pki
├── apiserver.crt
├── apiserver-kubelet-client.crt
└── front-proxy-client.crt
"
exit 1
esac
}
main "$@"
2.在 xuegod63 上执行如下：
1）给 update-kubeadm-cert.sh 证书授权可执行权限
[root@xuegod63 ~]#chmod +x update-kubeadm-cert.sh
2）执行下面命令，修改证书过期时间，把时间延长到 100 年
[root@xuegod63 ~]# ./update-kubeadm-cert.sh all
3）在 xuegod63 节点查询 Pod 是否正常,能查询出数据说明证书签发完成
kubectl get pods -n kube-system
可以看到都正常
验证证书有效时间是否延长到 100 年
[root@xuegod63 ~]#
openssl x509 -in /etc/kubernetes/pki/apiserver.crt -noout -text |grep Not
二、测试 k8s 集群的 DNS 解析和网络是否正常
#把 busybox-1-28.tar.gz 上传到 xuegod64 和 xuegod62 节点，手动解压
[root@xuegod64 ~]# ctr -n=k8s.io images import busybox-1-28.tar.gz
[root@xuegod62 ~]# ctr -n=k8s.io images import busybox-1-28.tar.gz
资料链接：https://pan.baidu.com/s/17e6AUn4Z-qPyTv6WnAjhtw?pwd=qrhq 提取码：qrhq
基于镜像创建一个pod，然后在pod 里面ping 百度查看网络通不通
[root@xuegod63 ~]#
kubectl run busybox --image busybox:1.28 --restart=Never --rm -it busybox -- sh/ # ping www.baidu.com
PING www.baidu.com (39.156.66.18): 56 data bytes
64 bytes from 39.156.66.18: seq=0 ttl=127 time=39.3 ms
#通过上面可以看到能访问网络，说明 calico 网络插件正常
/ # nslookup kubernetes.default.svc.cluster.local
Server: 10.96.0.10
Address 1: 10.96.0.10 kube-dns.kube-system.svc.cluster.local
Name: kubernetes.default.svc.cluster.local
Address 1: 10.96.0.1 kubernetes.default.svc.cluster.local
看到上面内容，说明 k8s 的 coredns 服务正常
