Configure corosync

Install corosync pacemaker in both server5 and server6

yum install corosync pacemaker -y

Edit the corosync configuration file in server5

mv /etc/corosync/corosync.conf.example /etc/corosync/corosync.conf

vim /etc/corosync/corosync.conf

# Please read the corosync.conf.5 manual page
compatibility: whitetank

totem {
        version: 2
        secauth: off    #Open authentication or not
        threads: 0  #When authentication is implemented, the number of concurrent threads is 0, which means the default
        interface {
                ringnumber: 0   #Ring number. Define a unique ring number for this network card to avoid heartbeat message ring sending
                bindnetaddr: 172.25.31.0        #Bound network address
                mcastaddr: 226.94.1.1   #Broadcast address
                mcastport: 31   #Broadcast port
                ttl: 1      #Only one broadcast out
        }
}

logging {
        fileline: off
        to_stderr: no
        to_logfile: yes
        to_syslog: yes
        logfile: /var/log/cluster/corosync.log
        debug: off
        timestamp: on
        logger_subsys {
                subsys: AMF
                debug: off
        }
}

amf {
        mode: disabled
}

service {   #Define a service to start pacemaker
  ver:  0   #pacemaker will be automatically started when corosync is started
  name: pacemaker
  use_mgmtd: yes
   }

scp /etc/corosync/corosync.conf 172.25.31.6:/etc/corosync/ #scp the configuration file to server6
/etc/init.d/corosync start  #Open corosync in both server5 and server6 

Configure cluster with crm

yum  localinstall crmsh-1.2.6-0.rc2.2.1.x86_64.rpm pssh-2.3.1-2.1.x86_64.rpm

Check the configuration file and an error will be reported, because we have not configured stonith at this time

crm_verify -LV  

Disable fence

crm
crm(live)# configure
crm(live)configure# property stonith-enabled=false
crm(live)configure# commit  #Submission

Check again at this time, no error is reported

crm_verify -LV

View current cluster
crm configure show

Set no quorum policy to ignore
In the two nodes, when the node fails to reach the legal votes, i.e. one of the two nodes is broken and cannot vote, and the normal node fails to reach the legal votes. In this case, if it is the default parameter, i.e. the normal machine cannot work, it needs to be ignore so that the normal machine can take over

crm(live)configure#  property no-quorum-policy=ignore
crm(live)configure# commit  

Add vip

crm(live)configure# primitive vip ocf:heartbeat:IPaddr2 params ip=172.25.31.100 cidr_netmask=24 op monitor interval=1min
crm(live)configure# commit

Add haproxy

crm(live)configure# primitive haproxy lsb:haproxy op monitor interval=1min
crm(live)configure# commit 

It is found that two resources are not running on the same node and resource drift occurs. Adding resource group can solve this problem

Add resource group

crm(live)configure# group westos vip haproxy
crm(live)configure# commit

Execute the crm node standby command on node server5 to disable the node
Resources will be transferred to server6

Execute the crm node online command on server5 to activate the node
Resources will not be transferred

Add fence

Ensure that the fence ﹣ virtd service on the host is turned on

stonith_admin -I    #Query fence device
stonith_admin -M -a fence_xvm   #View related configuration content 

We are going to use fence [XVM. If not, install the following software on server5 and Server6

yum install -y fence-virt.x86_64 fence-agents.x86_64 

Add fence resource

crm(live)configure# primitive vmfence stonith:fence_xvm params pcmk_host_map="server5:test5;server6:test6" op monitor interval=1min    
#Add fence resource, and map cluster node name and real server name
crm(live)configure# property stonith-enabled=true  #Open fence function
crm(live)configure# commit #Submission

Test:
Execute echo C > / proc / sysrq trigger in server5 to crash its kernel
server5 will restart automatically

Fence - H TEST6 - Manual fence test6