Kerberos How to Kerberize an Hadoop Cluster

Most Hadoop clusters adopt Kerberos as the authentication protocol

安装 KDC

• 启动Kerberos 认证需要安装 KDC 服务器和必要的软件。安装KDC 的命令可以在任何机器上执行。

yum -y install krb5-server krb5-lib krb5-auth-dialog krb5-workstation

• 接着，在集群中的其他节点上安装Kerberos client和命令

yum -y install krb5-lib krb5-auth-dialog krb5-workstation

• 编辑 KDC 配置的realms，AD(active directory)

　　krb5.conf 文件包含 KDCs、admin 服务器的地址，是当前 realm 和 Kerberos 应用的默认配置，该配置将主机名映射到 Kerberos realms。krb5.conf一般在/etc/krb5.conf

[logging]
 default = FILE:/var/log/krb5libs.log
 kdc = FILE:/var/log/krb5kdc.log
 admin_server = FILE:/var/log/kadmind.log

[libdefaults]
 default_realm = HADOOP.COM
 dns_lookup_realm = false
 dns_lookup_kdc = false
 ticket_lifetime = 24h
 renew_lifetime = 7d
 forwardable = true

[realms]
 HADOOP.COM = {
  kdc = node1.hadoop.com
  admin_server = node1.hadoop.com
 }

AD.COM = {
 kdc = windc.ad.com
 admin_server = windc.ad.com
}

[domain_realm]
 .hadoop.com = HADOOP.COM
 hadoop.com = HADOOP.COM
 .ad.com = AD.COM
 ad.com = AD.COM

[capaths]
 AD.COM = {
  HADOOP.COM = .
 }

realms: HADOOP_COM下的 kdc, admin_server是我们安装KDC的主机地址，AD.COM下的是 Domain Controller主机地址。

domain_realm: 提供domain name 或者主机名字到kerberos realms名字的转换。两者都必须小写。

capaths: cross-realm authentication中，不同 realms 之间需要数据库去创建authentication paths。 这部分定义存储。

• 编辑 kdc.conf，默认在 /var/Kerberos/krb5kdc/kdc.conf。包含 KDC 配置信息，包括发放 Kerberos tickets 时的默认值。

[realms]
  HADOOP.COM = {
  #master_key_type = aes256-cts
  acl_file = /var/kerberos/krb5kdc/kadm5.acl
  dict_file = /usr/share/dict/words
  admin_keytab = /var/kerberos/krb5kdc/kadm5.keytab
  supported_enctypes = aes256-cts:normal aes128-cts:normal des3-hmac-sha1:normal arcfour-hmac:normal des-hmac-sha1:normal des-cbc-md5:normal des-cbc-crc:normal
 }