This solution uses two VIP addresses, and the front-end uses 2 machines, each other is the master and backup. There are two machines working at the same time. When one of the machines fails, both The request from each machine is transferred to one machine, which is very suitable for the current architecture environment. Therefore, this solution is used to implement a high-availability architecture for the website.
Below we use the second configuration to demonstrate dual-master high-availability load balancing.
Group 1
VIP1: 192.168.36.100
Master nginx: 192.168.36.99
Prepare nginx: 192.168.36.86
Second Group
VIP2: 192.168.36.100
Main nginx: 192.168.36.86
Backup nginx: 192.168.36.99
web service:
web1: 192.168.36.215
web2: 192.168.36.80
1. nginx configuration (installation omitted)
worker_processes 1;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
sendfile on;
upstream web1 {
server 192.168.36.215:80 max_fails=3 fail_timeout=3s;
}
upstream web2 {
server 192.168.36.80:80 max_fails=3 fail_timeout=3s;
}
server {
listen 88;
server_name localhost;
location / {
root html;
index index.html index.htm;
proxy_pass http://web1;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
}
server {
listen 99;
server_name localhost;
location / {
root html;
index index.html index.htm;
proxy_pass http://web2;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
}
}
}web1
http://192.168.36.86:88/
http://192.168.36.99:88/
web2
http://192.168.36.86:99/
http://192.168.36.99:99/
2. Install and configure keepalived (installation omitted )
1)192.168.36.86 configuration
vi /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
monitor@3evip.cn
#failover@firewall.loc
}
notification_email_from tianwei7518@163.com
smtp_server smtp.163.com
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_script chk_nginx {
script "/etc/keepalived/chk_nginx.sh"
interval 2
weight 2
}
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 100
priority 50
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
track_script {
chk_nginx
}
virtual_ipaddress {
192.168.36.100
}
}
vrrp_instance VI_2 {
state MASTER
interface eth0
virtual_router_id 200
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
track_script {
chk_nginx
}
virtual_ipaddress {
192.168.36.200
}
}vi /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
notification_email {
monitor@3evip.cn
#failover@firewall.loc
}
notification_email_from tianwei7518@163.com
smtp_server smtp.163.com
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_script chk_nginx {
script "/etc/keepalived/chk_nginx.sh"
interval 2
weight 2
}
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 100
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
track_script {
chk_nginx
}
virtual_ipaddress {
192.168.36.100
}
}
vrrp_instance VI_2 {
state BACKUP
interface eth0
virtual_router_id 200
priority 50
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
track_script {
chk_nginx
}
virtual_ipaddress {
192.168.36.200
}
}vi /etc/keepalived/chk_nginx.sh
#!/bin/sh
#description: # 如果启动失败，则停止keepalived
status=$( ps -C nginx --no-heading| wc -l)
if [ "${status}" = "0" ]; then
/usr/local/nginx/sbin/nginx
status2=$( ps -C nginx --no-heading| wc -l)
if [ "${status2}" = "0" ]; then
service keepalived stop
fi
fi3. Start , test
Start nginx and keepalived respectively: /usr/local/nginx/sbin/nginx
service keepalived start
Visit:
web1
http://192.168. 36.100:88/
http://192.168.36.200:88/
web2
http://192.168.36.100:99/
http:// 192.168.36.200:99 /
can be accessed normally.
We can try to close a keepalived. Close keepalived on 192.168.36.86
service keepalived stop
View log:
tail - f /var/log/messages
192.168.36.86 log:
Feb 7 00:39:05 slave-d Keepalived[5738]: Stopping Keepalived v1.2.15 (02/07,2015) Feb 7 00:39:05 slave-d Keepalived_vrrp[5741]: VRRP_Instance(VI_2) sending 0 priority Feb 7 00:39:05 slave-d Keepalived_vrrp[5741]: VRRP_Instance(VI_2) removing protocol VIPs. Feb 7 00:39:05 slave-d Keepalived_healthcheckers[5740]: Netlink reflector reports IP 192.168.36.200 removed Feb 7 00:39:05 slave-d avahi-daemon[1823]: Withdrawing address record for 192.168.36.200 on eth0.
Feb 7 00:39:11 slave-c Keepalived_vrrp[25103]: VRRP_Instance(VI_2) Transition to MASTER STATE Feb 7 00:39:12 slave-c Keepalived_vrrp[25103]: VRRP_Instance(VI_2) Entering MASTER STATE Feb 7 00:39:12 slave-c Keepalived_vrrp[25103]: VRRP_Instance(VI_2) setting protocol VIPs. Feb 7 00:39:12 slave-c Keepalived_healthcheckers[25102]: Netlink reflector reports IP 192.168.36.200 added Feb 7 00:39:12 slave-c avahi-daemon[1832]: Registering new address record for 192.168.36.200 on eth0.IPv4. Feb 7 00:39:12 slave-c Keepalived_vrrp[25103]: VRRP_Instance(VI_2) Sending gratuitous ARPs on eth0 for 192.168.36.200 Feb 7 00:39:17 slave-c Keepalived_vrrp[25103]: VRRP_Instance(VI_2) Sending gratuitous ARPs on eth0 for 192.168.36.200
192.168.36. 86 Log:
Feb 7 00:40:42 slave-d Keepalived[6004]: Starting Keepalived v1.2.15 (02/07,2015) Feb 7 00:40:42 slave-d Keepalived[6005]: Starting Healthcheck child process, pid=6007 Feb 7 00:40:42 slave-d Keepalived[6005]: Starting VRRP child process, pid=6008 Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: Netlink reflector reports IP 192.168.36.86 added Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: Netlink reflector reports IP fe80::20c:29ff:fe6a:66ff added Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: Registering Kernel netlink reflector Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: Registering Kernel netlink command channel Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: Registering gratuitous ARP shared channel Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: Opening file '/etc/keepalived/keepalived.conf'. Feb 7 00:40:42 slave-d Keepalived_healthcheckers[6007]: Netlink reflector reports IP 192.168.36.86 added Feb 7 00:40:42 slave-d Keepalived_healthcheckers[6007]: Netlink reflector reports IP fe80::20c:29ff:fe6a:66ff added Feb 7 00:40:42 slave-d Keepalived_healthcheckers[6007]: Registering Kernel netlink reflector Feb 7 00:40:42 slave-d Keepalived_healthcheckers[6007]: Registering Kernel netlink command channel Feb 7 00:40:42 slave-d Keepalived_healthcheckers[6007]: Opening file '/etc/keepalived/keepalived.conf'. Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: Configuration is using : 44182 Bytes Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: Using LinkWatch kernel netlink reflector... Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: VRRP_Instance(VI_1) Entering BACKUP STATE Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: VRRP sockpool: [ifindex(2), proto(112), unicast(0), fd(10,11)] Feb 7 00:40:42 slave-d Keepalived_healthcheckers[6007]: Configuration is using : 7257 Bytes Feb 7 00:40:42 slave-d Keepalived_healthcheckers[6007]: Using LinkWatch kernel netlink reflector... Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: VRRP_Instance(VI_2) Transition to MASTER STATE Feb 7 00:40:42 slave-d Keepalived_vrrp[6008]: VRRP_Instance(VI_2) Received lower prio advert, forcing new election Feb 7 00:40:43 slave-d Keepalived_vrrp[6008]: VRRP_Instance(VI_2) Entering MASTER STATE Feb 7 00:40:43 slave-d Keepalived_vrrp[6008]: VRRP_Instance(VI_2) setting protocol VIPs. Feb 7 00:40:43 slave-d avahi-daemon[1823]: Registering new address record for 192.168.36.200 on eth0.IPv4. Feb 7 00:40:43 slave-d Keepalived_vrrp[6008]: VRRP_Instance(VI_2) Sending gratuitous ARPs on eth0 for 192.168.36.200 Feb 7 00:40:43 slave-d Keepalived_healthcheckers[6007]: Netlink reflector reports IP 192.168.36.200 added Feb 7 00:40:48 slave-d Keepalived_vrrp[6008]: VRRP_Instance(VI_2) Sending gratuitous ARPs on eth0 for 192.168.36.200
Feb 7 00:40:47 slave-c Keepalived_vrrp[25103]: VRRP_Instance(VI_2) Received higher prio advert Feb 7 00:40:47 slave-c Keepalived_vrrp[25103]: VRRP_Instance(VI_2) Entering BACKUP STATE Feb 7 00:40:47 slave-c Keepalived_vrrp[25103]: VRRP_Instance(VI_2) removing protocol VIPs. Feb 7 00:40:47 slave-c Keepalived_healthcheckers[25102]: Netlink reflector reports IP 192.168.36.200 removed Feb 7 00:40:47 slave-c avahi-daemon[1832]: Withdrawing address record for 192.168.36.200 on eth0.
After closing nginx, you can see that nginx starts immediately.
Reference article: tCentos6.5 Keepalived detailed explanation and high availability of Nginx services
Use Nginx+Keepalived to achieve high available load balancing
KEEPALIVED+nginx to achieve high availability and high availability and Dual-master node load balancing
nginx+keepalived realizes nginx dual-master high-availability load balancing
The above introduces Keepalived+nginx to achieve dual-master high-availability load balancing, including aspects of it. I hope it will be helpful to friends who are interested in PHP tutorials.
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