Heartbeat是High-Availability Linux Project (Linux下的高可用性項目)的産物，是一套提供防止業務主機因不可避免的意外性或計劃性當機問題的高可用性軟體。Heartbeat可以從Linux-HA 項目Web 站點免費獲得，它提供了所有HA （高可用性）系統所需要的基本功能，如啟動和停止資源、監測群集中系統的可用性、在群集中的節點間轉移共享IP 位址的所有者等。它通過串行線、以太網接口或同時使用兩者來監測特定服務（或多個服務）的運作狀況。
Heartbeat實作了HA 功能中的核心功能——心跳，将Heartbeat軟體同時安裝在兩台伺服器上，用于監視系統的狀态，協調主從伺服器的工作，維護系統的可用性。它能偵測伺服器應用級系統軟體、硬體發生的故障，及時地進行錯誤隔絕、恢複；通過系統監控、服務監控、IP自動遷移等技術實作在整個應用中無單點故障，簡單、經濟地確定重要的服務持續高可用性。
Heartbeat采用虛拟IP位址映射技術實作主從伺服器的切換對用戶端透明的功能。
實驗環境
centos6.5_x64
master eth0 192.168.1.128
eth1 192.168.1.129
slave eth0 192.168.1.130
eth1 192.168.1.131
vip 192.168.1.200
實驗軟體
epel-release-6-8.noarch.rpm
nginx.x86_64
heartbeat.x86_64
軟體安裝
rpm -ivh epel-release-6-8.noarch.rpm
yum install -y libnet heartbeat* nginx* glib*
vim /etc/hosts
centos6 192.168.1.128 添加兩行配置 master/slave相同操作 uname -n名字
centos6-1 192.168.1.130
less /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
centos6 192.168.1.128
ssh-keygen -t rsa master/slave 相同操作
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
scp /root/.ssh/id_rsa.pub [email protected]:/root/.ssh/authorized_keys
scp /root/.ssh/id_rsa.pub [email protected]:/root/.ssh/authorized_keys ssh信任
scp /root/aa.txt [email protected]:/root/
aa.txt 100% 0 0.0KB/s 00:00
scp /root/bb.txt [email protected]:/root/
bb.txt 100% 0 0.0KB/s 00:00
如果使用scp指令沒有提示輸入密碼表示ssh信任成功
service nginx start
chkconfig --level 35 nginx on
cd /usr/share/doc/heartbeat-3.0.4/ master/slave相同操作
cp authkeys ha.cf haresources /etc/ha.d/
vim /etc/ha.d/authkeys
#auth 1
#1 crc
#2 sha1 HI!
#3 md5 Hello! 找到
auth 3
3 md5 Hello! 改為 第一種是CRC循環備援校驗，第二種是SHA1雜湊演算法，第三種是MD3雜湊演算法
chmod 600 /etc/ha.d/authkeys
vim /etc/ha.d/haresources
centos6 192.168.1.200/24/eth0:0 nginx master端配置
centos6-1 192.168.1.200/24/eth0:0 nginx slave端配置
設定虛拟IP和對應的接口，并且指定啟動虛拟IP時啟動NGINX服務
vim /etc/ha.d/ha.cf
#debugfile /var/log/ha-debug 找到
debugfile /var/log/ha-debug 改為
touch /var/log/ha-debug
#logfile /var/log/ha-log 找到
logfile /var/log/ha-log 改為 日志檔案位置
touch /var/log/ha-log
logfacility local0
#keepalive 2 找到 檢查時間間隔
keepalive 2 改為
#deadtime 30 找到 設定死亡時間
deadtime 30 改為
#warntime 10 找到 設定告警時間
warntime 10 改為
#initdead 120 找到 設定初始化時間
initdead 20 改為
#udpport 694 找到
udpport 694 改為 udp端口号
#ucast eth0 192.168.1.2 找到
ucast eth1 192.168.1.131 改為 master端配置 eth1為心跳線ip 192.168.1.131為slave端ip
ucast eth1 192.168.1.129 改為 slave端配置 eth1為心跳線ip 192.168.1.129為master端ip
auto_failback on 找到 啟動搶占模式（主在挂了以後重新起來後備會自動切換成備）auto_failback auto_failback on 改為
node centos6 指定負載節點
node centos6-1
#ping 10.10.10.254 找到
ping 192.168.1.101 改為
#respawn hacluster /usr/lib/heartbeat/ipfail 找到
respawn hacluster /usr/lib64/heartbeat/ipfail 改為
chmod 600 /etc/ha.d/ha.cf
service heartbeat start master/slave端相同操作
netstat -tuplna | grep heartbeat
udp 0 0 0.0.0.0:56611 0.0.0.0:* 6831/heartbeat: wri
udp 0 0 0.0.0.0:694 0.0.0.0:* 6831/heartbeat: wri
ps -ef | grep heartbest
root 8034 8015 0 00:27 pts/0 00:00:00 grep heartbest
tail -f /var/log/ha-log
ip-request-resp(default)[12892]: 2017/10/25_01:25:59 received ip-request-resp 192.168.1.200/24/eth0:0 OK yes
ResourceManager(default)[12915]: 2017/10/25_01:26:00 info: Acquiring resource group: centos6 192.168.1.200/24/eth0:0 nginx
/usr/lib/ocf/resource.d//heartbeat/IPaddr(IPaddr_192.168.1.200)[12943]: 2017/10/25_01:26:00 INFO: Resource is stopped
ResourceManager(default)[12915]: 2017/10/25_01:26:00 info: Running /etc/ha.d/resource.d/IPaddr 192.168.1.200/24/eth0:0 start
IPaddr(IPaddr_192.168.1.200)[13076]: 2017/10/25_01:26:00 INFO: Adding inet address 192.168.1.200/24 with broadcast address 192.168.1.255 to device eth0 (with label eth0:0)
IPaddr(IPaddr_192.168.1.200)[13076]: 2017/10/25_01:26:00 INFO: Bringing device eth0 up
IPaddr(IPaddr_192.168.1.200)[13076]: 2017/10/25_01:26:00 INFO: /usr/libexec/heartbeat/send_arp -i 200 -r 5 -p /var/run/resource-agents/send_arp-192.168.1.200 eth0 192.168.1.200 auto not_used not_used
ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:45:17:73 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.129/24 brd 192.168.1.255 scope global eth1
inet6 fe80::20c:29ff:fe45:1773/64 scope link
3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:45:17:69 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.128/24 brd 192.168.1.255 scope global eth0
inet 192.168.1.200/24 brd 192.168.1.255 scope global secondary eth0:0
inet6 fe80::20c:29ff:fe45:1769/64 scope link
valid_lft forever preferred_lft forever master端
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:3d:5b:1b brd ff:ff:ff:ff:ff:ff
inet 192.168.1.130/24 brd 192.168.1.255 scope global eth0
inet6 fe80::20c:29ff:fe3d:5b1b/64 scope link
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:3d:5b:25 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.131/24 brd 192.168.1.255 scope global eth1
inet6 fe80::20c:29ff:fe3d:5b25/64 scope link
valid_lft forever preferred_lft forever slave端
看到eth0:0 說明配置成功
echo nginx_master > /usr/share/nginx/html/index.html master端
echo nginx_slave > /usr/share/nginx/html/index.html slave端
nginx -s reload
<a href="https://s2.51cto.com/oss/201710/25/750b3664141c30ea13eea498bc2278cb.jpg-wh_500x0-wm_3-wmp_4-s_2828371637.jpg" target="_blank"></a>
本文轉自 mailfile 51CTO部落格，原文連結：http://blog.51cto.com/mailfile/1975846，如需轉載請自行聯系原作者
![Web Service開發實戰[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)