LVS+Keepalived+nginx+单纯keepalived高可用
LVS+Keepalived实现高可用集群
LVS+Keepalived 介绍
LVS
LVS是Linux Virtual Server的简写，意即Linux虚拟服务器，是一个虚拟的服务器集群
系统。本项目在1998年5月由章文嵩博士成立，是中国国内最早出现的自由软件项 目之
一。目前有三种IP负载均衡技术（VS/NAT、VS/TUN和VS/DR）；
十种调度算法（rr|wrr|lc|wlc|lblc|lblcr|dh|sh|sed|nq）。
Keepalvied
Keepalived在这里主要用作RealServer的健康状态检查以及LoadBalance主机和BackUP
主机之间failover的实现
IP配置信息:
LVS-DR-Master 172.16.1.1
LVS-DR-BACKUP 172.16.1.8
LVS-DR-VIP 172.16.1.80
WEB1-Realserver01 172.16.1.2
WEB2-Realserver02 172.16.1.3
WEB3-Realserver03 172.16.1.4
一，安装LVS和Keepalvied软件包
1. Install ipvsadm
yum –y ipvsadm
2. 安装LVS和Keepalived
yum –y install gcc kernel-devel openssl-devel tar zxvf keepalived-1.1.15.tar.gz cd keepalived-1.1.15 ./configure -–sysconfdir=/etc/ --with-kernel-dir=/usr/src.kernel/2.6XXXX make && make install ln -s /usr/local/sbin/keepalived /sbin/ chkconfig --add keepalived chkconfig --level 2345 keepalived on service keepalived restart
二. 配置LVS实现负载均衡
lvs-dr
#!/bin/bash
VIP=172.16.1.80
./etc/rc.d/init.d/functions
case "$1" in
start)
ifconfig eth0:1 $VIP broadcast $VIP netmask 255.255.255.255 up
/sbin/route add -host $VIP dev eth0:1
echo "DirectoryServer Start OK"
;;
stop)
ipvsadm -C
ipvsadm -Z
ifconfig eth0:1 down
/sbin/route del $VIP >/dev/null 2>&1
echo "DirectoryServer Stop OK"
;;
*)
echo "Usage: $0 {start|stop}"
exit 1
esca
exit0
lvs-realserver
#!/bin/bash
VIP=10.207.238.82
. /etc/rc.d/init.d/functions
case "$1" in
start)
/sbin/ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up
/sbin/route add -host $VIP dev lo:0
echo "1" > /proc/sys/net/ipv4/conf/lo/arp_ignore
echo "2" > /proc/sys/net/ipv4/conf/lo/arp_announce
echo "1" > /proc/sys/net/ipv4/conf/all/arp_ignore
echo "2" > /proc/sys/net/ipv4/conf/all/arp_announce
sysctl -p >/dev/null 2>&1
echo "RealServer Start OK"
;;
stop)
/sbin/ifconfig lo:0 down
/sbin/route del $VIP >/dev/null 2>&1
echo "0" > /proc/sys/net/ipv4/conf/lo/arp_ignore
echo "0" > /proc/sys/net/ipv4/conf/lo/arp_announce
echo "0" > /proc/sys/net/ipv4/conf/all/arp_ignore
echo "0" > /proc/sys/net/ipv4/conf/all/arp_announce
;;
*)
echo "Usage: $0 {start|stop}"
exit 1
esac
exit 0
#end
三．利用Keepalvied結合lvs實現高可用实现负载均衡和和高可用性
1.配置在主负载均衡服务器上配置keepalived.conf
#vi /etc/keepalived/keepalived.conf (主调度器)
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
172.16.1.80
}
}
virtual_server 172.16.1.80 80 {
delay_loop 6
lb_algo wrr
lb_kind DR
persistence_timeout 60
protocol TCP
real_server 172.16.1.2 80 {
weight 3
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
real_server 172.16.1.3 80 {
weight 3
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
real_server 172.16.1.4 80 {
weight 3
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
在备用调度器上：
#vi /etc/keepalived/keepalived.conf (备调度器)
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 51
priority 90
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
172.16.1.80
}
}
virtual_server 172.16.1.80 80 {
delay_loop 6
lb_algo wrr
lb_kind DR
persistence_timeout 60
protocol TCP
real_server 172.16.1.2 80 {
weight 3
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
real_server 172.16.1.3 80 {
weight 3
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
real_server 172.16.1.4 80 {
weight 3
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 80
}
}
}
如果報錯
Jan 11 09:06:26 hnxz-vm-dg-s1 Keepalived_vrrp[2436]: ip address associated with VRID not present in received packet : 10.207.238.82 Jan 11 09:06:26 hnxz-vm-dg-s1 Keepalived_vrrp[2436]: one or more VIP associated with VRID mismatch actual MASTER advert
應該為virtual id 問題可以通過命令查看
tcpdump -nn -i any net 224.0.0.0/8
#watch ipvsadm –ln IP Virtual Server version 1.2.1 (size=4096) Prot LocalAddressort Scheduler Flags -> RemoteAddressort Forward Weight ActiveConn InActConn TCP 61.164.122.8:80 wrr persistent 60 -> 61.164.122.10:80 Route 3 0 0 -> 61.164.122.9:80 Route 3 0 0
#tail –f /var/log/message 监听日志，查看状态，测试LVS负载均衡及高可用性是否
有效。
5．停Master服务器的keepalived服务，查看BAKCUP服务器是否能正常接管服务。
6.单纯keepalived 实现高可用
! Configuration File for keepalived
global_defs {
notification_email {
[email protected]
}
notification_email_from [email protected]
smtp_server 10.195.225.126
smtp_connect_timeout 30
router_id LVS_DEVEL
}
vrrp_script chk_http_port {
script "/etc/keepalived/check-httpd.sh"
interval 2
weight 2
}
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 80
priority 100
authentication {
auth_type PASS
auth_pass eric
}
track_script {
chk_http_port
}
virtual_ipaddress {
10.207.238.82
}
}
检测脚本文件
vim /etc/keepalived/check-httpd.sh
#!/bin/bash # varsion 0.0.1 A=`ps -C httpd --no-header |wc -l` if [ $A -eq 0 ];then /usr/sbin/httpd -k start sleep 3 if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then killall keepalived fi fi
测试是否正常