1、keepalived的基本介紹node
一、keepalivd的核心功能就是在linux系統上經過vrrp協議實現LVS的高可用。linux
二、vrrp協議(虛擬冗餘路由協議)能夠將多個網關虛擬成一個網關,同時一組IP虛擬成VIP,及其MAC地址能夠同時虛擬化。算法
三、keepalived經過vrrp協議可以很好實現故障轉移,避免單點故障發生,主節點服務故障時,備節點可以取代主節點繼續提供服務。當故障節點恢復正常後,能自動將此節點加入到服務中。shell
四、vrrp協議狀態機制vim
五、keepalived服務的安裝,基於Centos6.4的實驗環境,直接使用1.2.7版本的rpm包安裝keepalived。bash
六、keepalived的主配置文件 /etc/keepalived/keepalived.conf
服務器
keepalived的服務腳本 /etc/rc.d/init.d/keepalivedssh
2、keepalived的配置文件ide
一、全局配置段oop
GLOBAL CONFIGURATION
global_defs { notification_email { acassen@firewall.loc failover@firewall.loc sysadmin@firewall.loc } notification_email_from Alexandre.Cassen@firewall.loc smtp_server 192.168.200.1 smtp_connect_timeout 30 router_id LVS_DEVEL }
定義郵件收發,靜態路由
二、keepalived的vrpp實例配置段
VRRPD CONFIGURATION
vrrp_instance VI_1 { state MASTER interface eth0 virtual_router_id 51 priority 100 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168.200.16 192.168.200.17 192.168.200.18 } }
虛擬路由的配置實例爲核心配置段
三、keepalived的LVS虛擬服務器配置段
LVS CONFIGURATION
virtual_server 192.168.200.100 443 { delay_loop 6 lb_algo rr lb_kind NAT nat_mask 255.255.255.0 persistence_timeout 50 protocol TCP real_server 192.168.201.100 443 { weight 1 SSL_GET { url { path / digest ff20ad2481f97b1754ef3e12ecd3a9cc } url { path /mrtg/ digest 9b3a0c85a887a256d6939da88aabd8cd } connect_timeout 3 nb_get_retry 3 delay_before_retry 3 } } }
3、keepalived實現LVS的高可用的準備環境
一、準備三個節點 ms/node1/node2。
二、在節點ms安裝ansible服務,實現節點node1/node2的互信。
[root@ms ~]# yum -y install ansible [root@ms ~]# ssh-keygen -t rsa -P '' [root@ms ~]# ssh-copy-id -i .ssh/id.rsa.pub root@node1.xiaozheng.com [root@ms ~]# ssh-copy-id -i .ssh/id.rsa.pub root@node2.xiaozheng.com
三、在節點node1/node2上安裝keepalived服務。
[root@ms ~]# ansible all -m shell -a "yum -y install keepalived"
四、去節點node1/node2查看keepalived的配置。
[root@node1 ~]# cd /etc/keepalived [root@node1 keepalived]# vim keepalived.conf [root@node2 ~]# cd /etc/keepalived [root@node2 keepalivd]# vim keepalived.conf
五、另啓動node1/node2的終端開啓日誌通知,隨時檢測。
[root@node1 ~]# tail -f /var/log/message [root@node2 ~]# tail -f /var/log/message
4、keepalived如何實如今狀態轉換時的通知
一、通知位置
vrrp_sync_group {
}
最經常使用的位置
vrrp_instance {
}
1)先定義一下全局配置段
global_defs { notification_email { root@localhost } notification_email_from msadmin@localhost smtp_server 127.0.0.1 smtp_connect_timeout 30 router_id LVS_DEVEL
2)定義相關控制機制
vrrp_script chk_main { script "[[ -f /etc/keepalived/down ]] && exit 1 || exit 0" interval 1 weight -2 }
3)接着定義vrrp實例段
節點node1的vrrp實例段配置
[root@node1 keepalived]# vim keepalived.conf vrrp_instance VI_1 { state MASTER interface eth0 virtual_router_id 63 priority 100 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 172.16.200.100 } track_script { chk_main }
節點node2vrrp實例段配置
[root@node2 keepalived]# vim keepalived.conf vrrp_instance VI_1 { state BACKUP interface eth0 virtual_router_id 63 priority 99 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 172.16.200.100 } track_script { chk_main }
二、通知方式
notify_master 主節點通知
notify_backup 備節點通知
notify_fault 故障點通知
4)在實例中能夠定義使用notify.sh腳本控制通知方式
notify_master "/etc/keepalived/notify.sh master" notify_backup "/etc/keepalived/notify.sh backup" notify_fault "/etc/keepalived/notify.sh fault"
* notify.sh實例腳本
#!/bin/bash # Author: MageEdu <linuxedu@foxmail.com> # description: An example of notify script vip=172.16.200.100 contact='root@localhost' notify() { mailsubject="`hostname` to be $1: $vip floating" mailbody="`date '+%F %H:%M:%S'`: vrrp transition, `hostname` changed to be $1" echo $mailbody | mail -s "$mailsubject" $contact } case "$1" in master) notify master exit 0 ;; backup) notify backup exit 0 ;; fault) notify fault exit 0 ;; *) echo 'Usage: `basename $0` {master|backup|fault}' exit 1 ;; esac
5)在節點ms上重啓node1/node2節點的keepalived服務並查看virtual_ipaddress所在節點
[root@ms ~]# ansible all -a "service keepalived restart" [root@ms ~]# ansible alol -m shell -a "ip addr show | grep eth0"
6)在主節點node1上編譯down文件,實現單點故障使virtual_ipaddress從主節點node1轉移到node2上去,並在節點ms查看節點之間VIP轉移情況
[root@node1 keepalived]# touch down [root@ms ~]# ansible all -m shell -a "ip addr show | grep eth0"
7) 恢復主節點node2,再次查看VIP的轉移情況
[root@node1 keepalived]# rm -rf down [root@ms ~]# ansible all -m shell -a "ip addr show | grep eth0"
5、如何配置ipvs
核心配置段爲 virtual server 定義虛擬主機
一、virtual_server IP port 定義虛擬主機IP地址及其端口
二、virtual_server fwmark int ipvs的防火牆打標,實現基於防火牆的LVS
三、virtual_server group string
四、lb_algo {rr|wrr|lc|wlc|lblc|lblcr} 定義LVS的調度算法
五、lb_kind {NAT|DR|TUN} 定義LVS的模型
六、presitence_timeout <INT> 定義支持持久鏈接的時長
七、protocol ipvs規則所能支持的協議
1)在vrrp_server段配置ipvs的實例
主節點node1 vrrp_server中的ipvs配置
[root@node1 keepalived]# vim keepalived.conf virtual_server 172.16.200.100 80 { delay_loop 6 lb_algo rr lb_kind DR nat_mask 255.255.0.0 persistence_timeout 0 protocol TCP real_server 172.16.200.8 80{ weight 1 HTTP_GET { url { path / status_code 200 } connect_timeout 3 nb_get_retry 3 delay_before_retry 3 } } }
備節點node2 vrrp_server中的ipvs配置
[root@node2 keepalived]# vim keepalived.conf virtual_server 172.16.200.100 80 { delay_loop 6 lb_algo rr lb_kind DR nat_mask 255.255.0.0 persistence_timeout 0 protocol TCP real_server 172.16.200.9 80{ weight 1 HTTP_GET { url { path / status_code 200 } connect_timeout 3 nb_get_retry 3 delay_before_retry 3 } } }
2)在節點ms上爲node1/node2節點安裝ipvsadm服務,並啓動主備節點的httpd服務
[root@ms ~]# ansible all -m shell -a "yum -y install ipvsadm" [root@ms ~]# ansible all -a "service httpd start"
3) 去節點node1/node2上查看相關的ipvs規則
[root@node1 keepalived]# ipvsadm -L -n [root@node2 keepalived]# ipvsadm -L -n
6、對特定的服務作高可用
一、監控服務
vrrp_script {
}
二、在vrrp實例中追蹤服務
track_script {
}
7、實現基於多虛擬路由的雙master模型
要實現基於多虛擬路由的master/master模型,則須要定義多個 vrrp_intance段的配置。
一、配置節點node1上的vrrp_intance段,定義兩個
[root@node1 keepalived]# vim keepalived.conf vrrp_instance VI_1 { state MASTER interface eth0 virtual_router_id 63 priority 100 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 172.16.200.100 } track_script { chk_main } vrrp_instance VI_2 { state BACKUP interface eth0 virtual_router_id 65 priority 99 advert_int 1 authentication { auth_type PASS auth_pass 21112 } virtual_ipaddress { 172.16.200.200 } track_srcipt { chk_main }
二、配置node2節點上vrrp_intance段,定義兩個
[root@node2 keepalived]# vim keepalived.conf vrrp_instance VI_1 { state BACKUP interface eth0 virtual_router_id 63 priority 99 advert_int 1 authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 172.16.200.100 } track_script { chk_main } vrrp_instance VI_2 { state MASTER interface eth0 virtual_router_id 65 priority 100 advert_int 1 authentication { auth_type PASS auth_pass 21112 } virtual_ipaddress { 172.16.200.200 } track_srcipt { chk_main }
三、使主節點node1的keepalived的服務停掉,在節點ms查看主備節點之間的VIP的轉,同理使備節點node2的keepalived的服務停掉並使node1的keepalived的服務啓動,於節點ms上查看主備節點之間VIP的轉移。
[root@node1 keepalived]# servive keepalived stop [root@ms ~]# ansible all -m shell -a "ip addr show | grep eth0" [root@node2 keepalived]# servive keepalived stop [root@node1 keepalived]# servive keepalived start [root@ms ~]# ansible all -m shell -a "ip addr show | grep eth0"