keepalived 2.0.12
官方：http://www.keepalived.org/
一 简介
Keepalived is a routing software written in C. The main goal of this project is to provide simple and robust facilities for loadbalancing and high-availability to Linux system and Linux based infrastructures. Loadbalancing framework relies on well-known and widely used Linux Virtual Server (IPVS) kernel module providing Layer4 loadbalancing. Keepalived implements a set of checkers to dynamically and adaptively maintain and manage loadbalanced server pool according their health. On the other hand high-availability is achieved by VRRP protocol. VRRP is a fundamental brick for router failover. In addition, Keepalived implements a set of hooks to the VRRP finite state machine providing low-level and high-speed protocol interactions. In order to offer fastest network failure detection, Keepalived implements BFD protocol. VRRP state transition can take into account BFD hint to drive fast state transition. Keepalived frameworks can be used independently or all together to provide resilient infrastructures.
keepalived是用c写的路由软件，使用vrrp协议（Virtual Router Redundancy Protocol）实现简单和健壮的负载均衡和高可用；
VRRP 将局域网的一组路由器（包括一个Master 即活动路由器和若干个Backup 即备份路由器）组织成一个虚拟路由器，称之为一个备份组。这个虚拟的路由器拥有自己的IP 地址10.100.10.1（这个IP 地址可以和备份组内的某个路由器的接口地址相同，相同的则称为ip拥有者），备份组内的路由器也有自己的IP 地址（如Master的IP 地址为10.100.10.2，Backup 的IP 地址为10.100.10.3）。局域网内的主机仅仅知道这个虚拟路由器的IP 地址10.100.10.1，而并不知道具体的Master 路由器的IP 地址10.100.10.2 以及Backup 路由器的IP 地址10.100.10.3。它们将自己的缺省路由下一跳地址设置为该虚拟路由器的IP 地址10.100.10.1。
二 安装
# yum install keepalived
主节点配置
# vi /etc/keepalived/keepalived.conf
vrrp_instance VI_1 {
state MASTER
interface eth0
mcast_src_ip 192.168.0.1
virtual_router_id 51
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.0.3
}
}
virtual_server 192.168.0.3 81 {
delay_loop 6
lb_algo rr
lb_kind DR
nat_mask 255.255.255.0
persistence_timeout 50
protocol TCP
#sorry_server 127.0.0.1 80
real_server 192.168.0.1 80 {
weight 1
}
real_server 192.168.0.2 80 {
weight 1
}
}
从节点修改配置
mcast_src_ip 192.168.0.2
state BACKUP
priority 50
如果开启iptables需要增加规则
# iptables -I INPUT -d 224.0.0.0/8 -j ACCEPT
# iptables -A INPUT -p vrrp -j ACCEPT
启动
# service keepalived start
查看vip
# ip a
查看tcp包
# tcpdump -p vrrp -n
参考：https://docs.oracle.com/cd/E37670_01/E41138/html/section_ksr_psb_nr.html
日志位于/var/log/messages，如果报错：
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: Registering Kernel netlink reflector
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: Registering Kernel netlink command channel
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: Registering gratuitous ARP shared channel
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: Opening file '/etc/keepalived/keepalived.conf'.
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: (VI_1): Cannot start in MASTER state if not address owner
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: Unable to load ipset library - libipset.so.11: cannot open shared object file: No such file or directory
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: VRRP_Instance(VI_1) removing protocol VIPs.
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: VRRP_Instance(VI_1) removing protocol iptable drop rule
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: Using LinkWatch kernel netlink reflector...
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: VRRP_Instance(VI_1) Entering BACKUP STATE
Jan 27 17:05:05 cdp-test-server-05 Keepalived_vrrp[26508]: VRRP sockpool: [ifindex(2), proto(112), unicast(0), fd(10,11)]
需要安装ipset
# yum install ipset
然后正常
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: Registering Kernel netlink reflector
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: Registering Kernel netlink command channel
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: Registering gratuitous ARP shared channel
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: Opening file '/etc/keepalived/keepalived.conf'.
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: (VI_1): Cannot start in MASTER state if not address owner
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: iptc_commit returned 0: No chain/target/match by that name
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) removing protocol VIPs.
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) removing protocol iptable drop rule
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: Using LinkWatch kernel netlink reflector...
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) Entering BACKUP STATE
Jan 27 21:40:35 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP sockpool: [ifindex(2), proto(112), unicast(0), fd(10,11)]
Jan 27 21:40:38 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) Transition to MASTER STATE
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) Entering MASTER STATE
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) setting protocol iptable drop rule
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) setting protocol VIPs.
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) Sending/queueing gratuitous ARPs on eth0 for 192.168.0.49
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:39 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:44 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:44 cdp-test-server-05 Keepalived_vrrp[7001]: VRRP_Instance(VI_1) Sending/queueing gratuitous ARPs on eth0 for 192.168.0.49
Jan 27 21:40:44 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:44 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:44 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49
Jan 27 21:40:44 cdp-test-server-05 Keepalived_vrrp[7001]: Sending gratuitous ARP on eth0 for 192.168.0.49