Kubernetes第一篇：集群安装及问题解决

一.目的：

安装kubernetes集群，为进行集群演练及实战做准备。

二.所需材料：

master(k8s1):10.10.11.12
node1(k8s2):10.10.10.217

三.安装步骤：

1.Master机器安装：

安装epel-release源

yum -y install epel-release

关闭防火墙服务和SELinx

systemctl stop firewalld
systemctl disable firewalld
setenforce 0

yum -y install etcd kubernetes-master

安装完成后，进入配置阶段，打开并编辑/etc/etcd/etcd.conf文件，如下所示：

#[Member]
ETCD_NAME=default #检查此处
#ETCD_CORS=""
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
#ETCD_WAL_DIR=""
#ETCD_LISTEN_PEER_URLS="http://localhost:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379" #此处一定要设置成0.0.0.0
#ETCD_MAX_SNAPSHOTS="5"
#ETCD_MAX_WALS="5"
ETCD_NAME="default"
#ETCD_SNAPSHOT_COUNT="100000"
#ETCD_HEARTBEAT_INTERVAL="100"
#ETCD_ELECTION_TIMEOUT="1000"
#ETCD_QUOTA_BACKEND_BYTES="0"
#ETCD_MAX_REQUEST_BYTES="1572864"
#ETCD_GRPC_KEEPALIVE_MIN_TIME="5s"
#ETCD_GRPC_KEEPALIVE_INTERVAL="2h0m0s"
#ETCD_GRPC_KEEPALIVE_TIMEOUT="20s"
#
#[Clustering]
#ETCD_INITIAL_ADVERTISE_PEER_URLS="http://localhost:2380"
ETCD_ADVERTISE_CLIENT_URLS="http://localhost:2379" #检查此处
#ETCD_DISCOVERY=""
#ETCD_DISCOVERY_FALLBACK="proxy"
#ETCD_DISCOVERY_PROXY=""
#ETCD_DISCOVERY_SRV=""
#ETCD_INITIAL_CLUSTER="default=http://localhost:2380"
#ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
#ETCD_INITIAL_CLUSTER_STATE="new"
#ETCD_STRICT_RECONFIG_CHECK="true"
#ETCD_ENABLE_V2="true"

备注：ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379" #此处一定要设置成0.0.0.0，否则node启动时会报错：Failed to start Flanneld overlay address etcd agent.

编辑核心配置文件：/etc/kubernetes/apiserver

###
# kubernetes system config
#
# The following values are used to configure the kube-apiserver
#

# The address on the local server to listen to.
KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0" #此处默认为127.0.0.1,但一定要设置成0.0.0.0

# The port on the local server to listen on.
KUBE_API_PORT="--port=8080"

# Port minions listen on
KUBELET_PORT="--kubelet-port=10250"

# Comma separated list of nodes in the etcd cluster
KUBE_ETCD_SERVERS="--etcd-servers=http://127.0.0.1:2379"

# Address range to use for services
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"

# default admission control policies
KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota"

# Add your own!
KUBE_API_ARGS=""

备注：KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0" #此处默认为127.0.0.1,但一定要设置成0.0.0.0，否则node1无法注册成功，主机运行kubectl get node时，node1状态为：NotReady

启动etcd、kube-apiserver、kube-controller-manager、kube-scheduler等服务，并设置随机启动：

for SERVICES in etcd kube-apiserver kube-controller-manager kube-scheduler; do systemctl restart $SERVICES;systemctl enable $SERVICES;systemctl status $SERVICES ; done

在etcd中设置flannel网络，请注意，此步骤需要在上面启动的情况下进行：

etcdctl mk /atomic.io/network/config '{"Network":"172.17.0.0/16"}'

master机器安装完成。

2.node1机器安装：

首先安装flannel和kubernetes-node：

yum -y install flannel kubernetes-node

然后配置flannel的ETCD，配置文件地址：/etc/sysconfig/flanneld

FLANNEL_ETCD="http://10.10.11.12:2379"
FLANNEL_ETCD_KEY="/atomic.io/network"

配置Kubernetes的配置文件：/etc/kubernetes/config

###
# kubernetes system config
#
# The following values are used to configure various aspects of all
# kubernetes services, including
#
#   kube-apiserver.service
#   kube-controller-manager.service
#   kube-scheduler.service
#   kubelet.service
#   kube-proxy.service
# logging to stderr means we get it in the systemd journal
KUBE_LOGTOSTDERR="--logtostderr=true"

# journal message level, 0 is debug
KUBE_LOG_LEVEL="--v=0"

# Should this cluster be allowed to run privileged docker containers
KUBE_ALLOW_PRIV="--allow-privileged=false"

# How the controller-manager, scheduler, and proxy find the apiserver
KUBE_MASTER="--master=http://10.10.11.12:8080" #只需要修改此处的IP为masterIP即可。

及配置文件：/etc/kubernetes/kubelet

###
# kubernetes kubelet (minion) config

# The address for the info server to serve on (set to 0.0.0.0 or "" for all interfaces)
KUBELET_ADDRESS="--address=127.0.0.1" #此处应配置为0.0.0.0，但不修改也能正常运行。

# The port for the info server to serve on
KUBELET_PORT="--port=10250" #打开端口

# You may leave this blank to use the actual hostname
KUBELET_HOSTNAME="--hostname-override=10.10.10.217" #此处为本机k8s2的IP

# location of the api-server
KUBELET_API_SERVER="--api-servers=http://10.10.11.12:8080" #master机器IP

# pod infrastructure container
KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest"

# Add your own!
KUBELET_ARGS=""

设置完成后，启动kube-proxy、kubelet、docker、flanneld等服务，并设置随机启动。

for SERVICES in kube-proxy kubelet docker flanneld;do systemctl restart $SERVICES;systemctl enable $SERVICES;systemctl status $SERVICES; done

四.集群验证：

验证Kubernetes是否启动成功，在master机器上运行：

[root@k8s1 ~]# kubectl get node
NAME           STATUS    AGE
10.10.10.217   Ready     22m
[root@k8s1 ~]# 

 参考：k8s入门系列之集群安装篇