OpenShift环境中手工模式添加etcd server

模拟备份和恢复，在现有的集群环境,单master(etcd), infra和node上面添加另外一台机器作为etcd Server.

基于OpenShift 3.11版本，详情可以参考

https://docs.openshift.com/container-platform/3.11/admin_guide/assembly_restoring-cluster.html#restoring-etcd-v3-snapshot

为了减少步骤，先clone那台master出来成为etcd1,然后修改ip，主机名，然后将上面的服务移除

# mkdir -p /etc/origin/node/pods-stopped
# mv /etc/origin/node/pods/* /etc/origin/node/pods-stopped/

然后开始具体步骤：

• 修改双方机器的/etc/hosts加入节点
• 生成新节点所需要的证书

master节点上操作

export NEW_ETCD_HOSTNAME="etcd1.example.com"
export NEW_ETCD_IP="192.168.56.109"

export CN=$NEW_ETCD_HOSTNAME
export SAN="IP:${NEW_ETCD_IP}, DNS:${NEW_ETCD_HOSTNAME}"
export PREFIX="/etc/etcd/generated_certs/etcd-$CN/"
export OPENSSLCFG="/etc/etcd/ca/openssl.cnf"

# mkdir -p ${PREFIX}

# openssl req -new -config ${OPENSSLCFG} \
    -keyout ${PREFIX}server.key  \
    -out ${PREFIX}server.csr \
    -reqexts etcd_v3_req -batch -nodes \
    -subj /CN=$CN

# openssl ca -name etcd_ca -config ${OPENSSLCFG} \
    -out ${PREFIX}server.crt \
    -in ${PREFIX}server.csr \
    -extensions etcd_v3_ca_server -batch

# openssl req -new -config ${OPENSSLCFG} \
    -keyout ${PREFIX}peer.key \
    -out ${PREFIX}peer.csr \
    -reqexts etcd_v3_req -batch -nodes \
    -subj /CN=$CN

# openssl ca -name etcd_ca -config ${OPENSSLCFG} \
  -out ${PREFIX}peer.crt \
  -in ${PREFIX}peer.csr \
  -extensions etcd_v3_ca_peer -batch

将配置etcd.conf和ca.crt拷贝到master下为新的etcd节点配置的路径

# cp /etc/etcd/etcd.conf ${PREFIX}
# cp /etc/etcd/ca.crt ${PREFIX}

• 添加节点，在master机器上操作

先member list一下，确保没有localhost

etcdctl --cert-file=/etc/etcd/peer.crt \
    --key-file=/etc/etcd/peer.key \
    --ca-file=/etc/etcd/ca.crt \
    --peers="https://192.168.56.103:2379"    member list

etcdctl -C https://192.168.56.103:2379 \
  --ca-file=/etc/etcd/ca.crt     \
  --cert-file=/etc/etcd/peer.crt     \
  --key-file=/etc/etcd/peer.key member add ${NEW_ETCD_HOSTNAME} https://${NEW_ETCD_IP}:2380

Member 2bc199c384f701e3 added to cluster e99c0083931d3d79

ETCD_NAME="etcd1.example.com"
ETCD_INITIAL_CLUSTER="etcd1.example.com=https://192.168.56.109:2380,master.example.com=https://192.168.56.103:2380"
ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.56.109:2380"
ETCD_INITIAL_CLUSTER_STATE="existing"

• 修改配置

修改${PREFIX}/etcd.conf的各种值，按照上面的输出，主要是包括这些字段

ETCD_NAME

ETCD_INITIAL_CLUSTER

ETCD_INITIAL_CLUSTER_STATE

ETCD_LISTEN_PEER_URLS
ETCD_LISTEN_CLIENT_URLS
ETCD_INITIAL_ADVERTISE_PEER_URLS
ETCD_ADVERTISE_CLIENT_URLS

打包拷贝到新的etcd机器

# tar -czvf /etc/etcd/generated_certs/${CN}.tgz -C ${PREFIX} .
# scp /etc/etcd/generated_certs/${CN}.tgz ${CN}:/tmp/

• 新的etcd的机器上操作

停进程

# mkdir -p /etc/origin/node/pods-stopped
# mv /etc/origin/node/pods/* /etc/origin/node/pods-stopped/

• 删除现有数据

# rm -Rf /etc/etcd/*
# rm -Rf /var/lib/etcd/*

# tar xzvf /tmp/etcd0.example.com.tgz -C /etc/etcd/

# chown -R etcd.etcd /etc/etcd/*
# chown -R etcd.etcd /var/lib/etcd/

检查一下这些数据的时间点

• 启动新的etcd

# cp /etc/origin/node/pods-stopped/etcd.yaml  /etc/origin/node/pods/

通过master-logs观察数据

/usr/local/bin/master-logs etcd etcd -f

在/var/lib/etcd下会同步一份新的数据

无误后检查

相同步骤添加另一个Server.

etcd数据恢复

如果是原来就有3个Etcd Server,可以先用snapshot.db恢复第一台，然后基于member add添加另外一台，启动另外那台就可，

不需要配置证书等步骤。