keepalived
=============================

架构
-----------------------------

配置容器的静态IP
-----------------------------

.. code-block:: bash

    vim /etc/network/interfaces

原始文件内容：

.. code-block:: text

    auto eth0
    iface eth0 inet dhcp
    hostname $(hostname)

需要修改成：

.. code-block:: text

    auto eth0
    hostname $(hostname)
    iface eth0 inet static
        address 10.196.126.12
        netmask 255.255.255.0
        gateway 10.196.126.1
        dns-nameservers 8.8.8.8 8.8.4.4

.. code-block:: bash

    /etc/init.d/networking restart
    # 或者
    # 重启lxc容器。

nginx-1
-----------------------------

IP: 10.196.126.12

.. code-block:: 

    apk add nginx
    service nginx start
    apk add keepalived
    mkdir -p /etc/keepalived
    vi /etc/keepalived/keepalived.conf

.. code-block:: 

    vrrp_instance VI_1 {
        state MASTER
        interface eth0
        virtual_router_id 51
        priority 100
        advert_int 1
        authentication {
            auth_type PASS
            auth_pass my_secret_password
        }
        virtual_ipaddress {
            10.196.126.14
        }
    }

解释：

.. code-block:: 

    vrrp_instance VI_1 {
        state MASTER                    # 指定此节点为主节点
        interface eth0                  # 监控的网络接口
        virtual_router_id 51            # VRID（虚拟路由器ID），在所有节点上必须相同
        priority 100                    # 优先级，数字越大，优先级越高
        advert_int 1                    # 通告间隔时间（秒），各节点间同步信息的时间间隔
        authentication {
            auth_type PASS              # 认证类型
            auth_pass my_secret_password # 认证密码，确保所有节点一致
        }
        virtual_ipaddress {
            10.196.126.14               # 虚拟IP地址（VIP），要在节点间切换的IP
        }
    }

.. code-block:: 

    service keepalived start

nginx-2
-----------------------------

IP: 10.196.126.13

.. code-block:: 

    apk add nginx
    service nginx start
    apk add keepalived
    mkdir -p /etc/keepalived
    vi /etc/keepalived/keepalived.conf

.. code-block:: 

    vrrp_instance VI_1 {
        state BACKUP
        interface eth0
        virtual_router_id 51
        priority 90
        advert_int 1
        authentication {
            auth_type PASS
            auth_pass my_secret_password
        }
        virtual_ipaddress {
            10.196.126.14
        }
    }

解释： 

.. code-block:: 

    vrrp_instance VI_1 {
        state BACKUP                    # 指定此节点为备节点
        interface eth0                  # 监控的网络接口
        virtual_router_id 51            # VRID（虚拟路由器ID），在所有节点上必须相同
        priority 90                     # 优先级，数字越大，优先级越高
        advert_int 1                    # 通告间隔时间（秒），各节点间同步信息的时间间隔
        authentication {
            auth_type PASS              # 认证类型
            auth_pass my_secret_password # 认证密码，确保所有节点一致
        }
        virtual_ipaddress {
            10.196.126.14               # 虚拟IP地址（VIP），要在节点间切换的IP
        }
    }

.. code-block:: 

    service keepalived start