如何创建etcd双向通信证书

# 安装证书生成软件
wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64 -O /usr/bin/cfssl
wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64 -O /usr/bin/cfssl-json
wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64 -O /usr/bin/cfssl-certinfo
chmod +x /usr/bin/cfssl*

# 创建证书签发目录
mkdir -p /opt/certs

# 创建跟证书
/opt/certs/ca-csr.json

{
    "CN": "OldboyEdu",
    "hosts": [
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "ST": "beijing",
            "L": "beijing",
            "O": "od",
            "OU": "ops"
        }
    ],
    "ca": {
        "expiry": "175200h"
    }
}

# 根证书生成
cfssl gencert -initca ca-csr.json | cfssl-json -bare ca


# 创建etcd证书配置
cat /opt/certs/ca-config.json

{
    "signing": {
        "default": {
            "expiry": "175200h"
        },
        "profiles": {
            "server": {
                "expiry": "175200h",
                "usages": [
                    "signing",
                    "key encipherment",
                    "server auth"
                ]
            },
            "client": {
                "expiry": "175200h",
                "usages": [
                    "signing",
                    "key encipherment",
                    "client auth"
                ]
            },
            "peer": {
                "expiry": "175200h",
                "usages": [
                    "signing",
                    "key encipherment",
                    "server auth",
                    "client auth"
                ]
            }
        }
    }
}

cat /opt/certs/etcd-peer-csr.json

注意：只支持IP/不支持网段

{
    "CN": "k8s-etcd",
    "hosts": [
        "10.4.7.11",
        "10.4.7.12",
        "10.4.7.21",
        "10.4.7.22"
    ],
    "key": {
        "algo": "rsa",
        "size": 2048
    },
    "names": [
        {
            "C": "CN",
            "ST": "beijing",
            "L": "beijing",
            "O": "od",
            "OU": "ops"
        }
    ]
}

# 生成etcd双向通信证书

cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=peer etcd-peer-csr.json |cfssl-json -bare etcd-pee

来源：https://www.cnblogs.com/ipyanthony/p/12011893.html