• 資源配置的自動同步和版本管理。
• 靈活的資源和 fencing 模式可與使用者環境更緊密地對應。
• 可使用 fencing 恢復資源層失敗。
• 基於時間的配置選項。
• 在多節點中運行同一資源的能力。例如：網頁伺服器或者叢集檔案系統。
• 在兩個不同模式之一的多個節點中運行同一資源的能力。例如：同步資源和目標。
• Pacemaker 不需要分散式鎖管理程式。
• 仲裁丟失或者形成多個分割槽時的可配置行為。

Pacemaker 配置系統，也稱 pcs，替換了 ccs、ricci 和 luci作為統一的叢集配置和管理工具。pcs 的優點包括：
• 命令列工具。
• 可輕鬆自我啟動叢集，即初始化叢集並使其開始執行。
• 可配置叢集選項。
• 可新增、刪除或者修改資源及其之間的關係。
 

一、叢集配置

本文采用2臺機器

192.168.122.194

192.168.122.137

關閉防火牆、SELINUX

[[email protected] ~]# systemctl disable firewalld

[[email protected] ~]# vim /etc/selinux/config 

SELINUX=disabled

修改主機名及時間同步

[[email protected] ~]# hostnamctl set-hostname node1

[[email protected] ~]# yum -y install ntp

[[email protected] ~]# ntpdate cn.pool.ntp.org

[[email protected] ~]# ssh-keygen -f /root/.ssh/id_rsa -N ""

[[email protected] ~]# mv /root/.ssh/{id_rsa.pub,authorized_keys}

[[email protected] ~]# scp -r /root/.ssh node2:/root/

[[email protected]
 
 ~]# ls /root/.ssh/

authorized_keys  id_rsa  known_hosts

[[email protected] ~]# vim /etc/hosts

192.168.122.194 node1
192.168.122.137 node2

[[email protected] ~]# yum -y install pcs pacemaker corosync fence-agents-all

[[email protected] ~]# systemctl start pcsd.service && systemctl enable pcsd.servic
[[email protected] ~]# passwd hacluster

任意節點

[[email protected] ~]# pcs cluster auth node1 node2

Username: hacluster
Password: 
node1: Authorized
node2: Authorized

建立叢集

[[email protected] ~]# pcs cluster setup --start --name abel_cluster \
> node1 node2
Destroying cluster on nodes: node1, node2...
node2: Stopping Cluster (pacemaker)...
node1: Stopping Cluster (pacemaker)...
node1: Successfully destroyed cluster
node2: Successfully destroyed cluster


Sending 'pacemaker_remote authkey' to 'node1', 'node2'
node1: successful distribution of the file 'pacemaker_remote authkey'
node2: successful distribution of the file 'pacemaker_remote authkey'
Sending cluster config files to the nodes...
node1: Succeeded
node2: Succeeded


Starting cluster on nodes: node1, node2...
node2: Starting Cluster...
node1: Starting Cluster...


Synchronizing pcsd certificates on nodes node1, node2...
node1: Success
node2: Success
Restarting pcsd on the nodes in order to reload the certificates...
node1: Success
node2: Success
[[email protected] ~]# pcs cluster enable --all
node1: Cluster Enabled
node2: Cluster Enabled

啟動叢集

[[email protected] ~]# pcs cluster start --all

[[email protected] ~]# pcs cluster enable --all

node1: Cluster Enabled
node2: Cluster Enabled

[[email protected] ~]# pcs cluster status
Cluster Status:
 Stack: corosync
 Current DC: node1 (version 1.1.16-12.el7_4.4-94ff4df) - partition with quorum
 Last updated: Wed Nov  8 11:41:06 2017
 Last change: Wed Nov  8 11:40:05 2017 by hacluster via crmd on node1
 2 nodes configured
 0 resources configured


PCSD Status:
  node1: Online
  node2: Online

[[email protected] ~]# corosync-cfgtool -s

Printing ring status.
Local node ID 1
RING ID 0
	id	= 192.168.122.171
	status	= ring 0 active with no faults

[[email protected] ~]# corosync-cmapctl | grep members

runtime.totem.pg.mrp.srp.members.1.config_version (u64) = 0
runtime.totem.pg.mrp.srp.members.1.ip (str) = r(0) ip(192.168.122.171) 
runtime.totem.pg.mrp.srp.members.1.join_count (u32) = 1
runtime.totem.pg.mrp.srp.members.1.status (str) = joined
runtime.totem.pg.mrp.srp.members.2.config_version (u64) = 0
runtime.totem.pg.mrp.srp.members.2.ip (str) = r(0) ip(192.168.122.11) 
runtime.totem.pg.mrp.srp.members.2.join_count (u32) = 1
runtime.totem.pg.mrp.srp.members.2.status (str) = joined

[[email protected] ~]# pcs status corosync 

Membership information
----------------------
    Nodeid      Votes Name
         2          1 node2
         1          1 node1 (local)

如果沒有Fence，建議禁用STONITH

[[email protected] ~]# pcs property set stonith-enabled=false

正常叢集Quorum（法定）需要半數以上的票數，如果是雙節點的叢集

[[email protected] ~]# pcs property set no-quorum-policy=ignore
[[email protected] ~]# crm_verify -L -V

測試

[[email protected] ~]# pcs resource create VirtualIP IPaddr2 ip=192.168.0.99 cidr_netmask=32 nic=eth0 op monitor interval=30s
[[email protected] ~]# pcs resource show
Resource Group: apachegroup
web_lvm	(ocf::heartbeat:LVM):	Stopped
 VirtualIP	(ocf::heartbeat:IPaddr2):	Started node
[[email protected] ~]# ip a
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
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 52:54:a8:ab:a3:c8 brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.194/24 brd 192.168.122.255 scope global dynamic eth0
       valid_lft 3111sec preferred_lft 3111sec
    inet 192.168.0.99/32 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::5054:a8ff:feab:a3c8/64 scope link 
       valid_lft forever preferred_lft forever