Haproxy+kept build 01

---

Preface

Installation mode ：yum
Server environment ：Centos7.5
haproxy edition ：1.5.18
The goal is ： Realize two haproxy Dual server hot standby , To solve the problem haproxy Server single point of failure , Realize the high availability of the server ;

---

1、 preparation

1.1 Server preparation

• haproxy11：192.168.45.11
• haproxy12：192.168.45.12
• fictitious ip Address ：192.168.145.10

1.2 Turn off firewall

#  View firewall status , If the state is “running”, So close it ！
firewall-cmd --state
#  Turn off firewall 
systemctl stop firewalld

1.3 Set up selinux

setenforce 0

2、haproxy Installation and configuration

haproxy11 And haproxy12 The installation and configuration are completely consistent

2.1 install

yum -y install haproxy
cp /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg.bak
vi /etc/haproxy/haproxy.cfg

2.2 haproxy.cfg To configure

#---------------------------------------------------------------------
# Example configuration for a possible web application. See the
# full configuration options online.
#
# http://haproxy.1wt.eu/download/1.4/doc/configuration.txt
#
#---------------------------------------------------------------------

#---------------------------------------------------------------------
# Global settings
#---------------------------------------------------------------------
global
    log         127.0.0.1 local1
    chroot      /var/lib/haproxy
    pidfile     /var/run/haproxy.pid
    maxconn     4000
    user        haproxy
    group       haproxy
    daemon
    stats socket /var/lib/haproxy/stats

defaults
    mode                    http
    log                     global
    option                  httplog
    option                  dontlognull
    option http-server-close
    option forwardfor       except 127.0.0.0/8
    option                  redispatch
    retries                 3
    timeout http-request    10s
    timeout queue           1m
    timeout connect         10s
    timeout client          1m
    timeout server          1m
    timeout http-keep-alive 10s
    timeout check           10s
    maxconn                 3000
listen stats
        bind          0.0.0.0:8888
        mode          http
        stats         enable
        stats         hide-version
        stats uri     /haproxystats
        stats realm   Haproxy\ stats
        stats auth    admin:admin
        stats admin   if TRUE

frontend http-in
        bind 0.0.0.0:5672
        mode tcp
        log global
        option httplog
        option httpclose
        default_backend rabbitmq-server

backend rabbitmq-server
        mode tcp
        balance roundrobin
        server  node1 192.168.45.201:5672 maxconn 2000 weight 1  check inter 5s rise 2 fall 2
        server  node2 192.168.45.202:5672 maxconn 2000 weight 1  check inter 5s rise 2 fall 2
        server  node3 192.168.45.203:5672 maxconn 2000 weight 1  check inter 5s rise 2 fall 2

2.3 rsyslog Log configuration

vi /etc/rsyslog.conf

# Provides UDP syslog reception
#  Open the following configuration 
$ModLoad imudp
$UDPServerRun 514

# Provides TCP syslog reception
#  Open the following configuration 
$ModLoad imtcp
$InputTCPServerRun 514

# Save boot messages also to boot.log
#  Add the following configuration 
local1.*                          /var/log/haproxy/haproxy.log

2.4 Start the service

#  Create log folder 
mkidr /var/log/haproxy
#  Start log service 
systemctl restart rsyslog.service
#  start-up haproxy
systemctl start haproxy
#  see haproxy  start log 
cat /var/log/haproxy/haproxy.log
#  Real-time view haproxy  journal 
tail -f /var/log/haproxy.log

2.5 Login and verify

haproxy11 Manage background address ：192.168.45.11:8888/haproxystats
haproxy12 Manage background address ：192.168.45.12:8888/haproxystats
account number ：admin
password ：admin

3、 Installation and configuration keepalived

stay haproxy11 And haproxy12 Install separately in keepalived

3.1 install keepalived

yum -y install keepalived

3.2 To configure keepalived（haproxy11）

cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak
vi /etc/keepalived/keepalived.conf

keepalived.conf Configure the content

! Configuration File for keepalived

global_defs {
    
   router_id director1
}
vrrp_script check_haproxy {
    
   script "/etc/keepalived/haproxy_chk.sh"
   interval 5
}

vrrp_instance VI_1 {
    
    state MASTER
    interface ens33
    virtual_router_id 80
    priority 100
    advert_int 1
    authentication {
    
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
    
        192.168.45.10
    }
    track_script {
    
        check_haproxy
    }
}

3.3 To configure keepalived（haproxy12）

cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak
vi /etc/keepalived/keepalived.conf

keepalived.conf Configure the content

! Configuration File for keepalived

global_defs {
    
   router_id director2
}
vrrp_script check_haproxy {
    
   script "/etc/keepalived/haproxy_chk.sh"
   interval 5
}

vrrp_instance VI_1 {
    
    state BACKUP
    interface ens33
    virtual_router_id 80
    priority 50
    advert_int 1
    authentication {
    
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
    
        192.168.45.10
    }
    track_script {
    
        check_haproxy
    }
}

3.4 Configure health detection scripts haproxy_chk.sh

haproxy11 And haproxy12 The configuration in is the same ！

#!/usr/bin/env bash
# test haproxy server running
systemctl status haproxy.service &>/dev/null
if [ $? -ne 0 ];then
    systemctl start haproxy.service &>/dev/null
    sleep 5
    systemctl status haproxy.service &>/dev/null
    if [ $? -ne 0 ];then
        systemctl stop keepalived
    fi
fi

3.5 Verify virtual IP

systemctl start keepalived
#  stay haproxy11  and haproxy12  In case of successful startup , Respectively in haproxy11  and haproxy12 Run the following command in 
ip addr

Stop haproxy11 The server stay haproxy12 View in ip Address ：

4、 Related startup commands

firewall-cmd --state
systemctl stop firewalld && setenforce 0
systemctl restart rsyslog.service
systemctl start haproxy
systemctl start keepalived
systemctl status haproxy

5、 Problems encountered

5.1 Network card problem

When it's done haproxy + keepalived After the dual active hot standby server , It was found during the test that , When one of them is completely shut down haproxy After the server , Find out ：IP The address cannot be displayed normally , namely ：ip addr And other related commands , There is no previous configuration IP Address information , And use commands ：systemctl restart network.service Will report a mistake ：

Solution ：

#  see NetworkManager state 
systemctl status NetworkManager
# NetworkManager and network There are two different services , They are conflicting . The most fundamental solution is to NetworkManager Service stopped 
#  Pause ,  After the server restarts, it will still start 
systemctl stop NetworkManager
#  Permanent stop 
systemctl disable NetworkManager
#  Start network service 
systemctl start network.service
#  see IP Address ,  See if it works . If it still doesn't work , Then restart the server ！
ip  addr

5.2 keepalived Service issues

When it's done haproxy + keepalived After the dual active hot standby server , It was found during the test that , occasionally keepalived Even if the service is running , Still can't use vip visit haproxy The address of the server . Then you may need to restart keepalived service ：

systemctl restart keepalived