以ipvsadm v1.27版本为例说明ipvsadm命令使用方式，对应内核ipvs版本v1.2.1

# ipvsadm -h
ipvsadm v1.27 2008/5/15 (compiled with popt and IPVS v1.2.1)
Usage:
  ipvsadm -A|E -t|u|f service-address [-s scheduler] [-p [timeout]] [-M netmask] [--pe persistence_engine] [-b sched-flags] 
  ipvsadm -D -t|u|f service-address
  ipvsadm -C
  ipvsadm -R
  ipvsadm -S [-n]
  ipvsadm -a|e -t|u|f service-address -r server-address [options]
  ipvsadm -d -t|u|f service-address -r server-address
  ipvsadm -L|l [options]
  ipvsadm -Z [-t|u|f service-address]
  ipvsadm --set tcp tcpfin udp
  ipvsadm --start-daemon state [--mcast-interface interface] [--syncid sid]
  ipvsadm --stop-daemon state
  ipvsadm -h

Commands:
Either long or short options are allowed.
  --add-service     -A        add virtual service with options
  --edit-service    -E        edit virtual service with options
  --delete-service  -D        delete virtual service
  --clear           -C        clear the whole table
  --restore         -R        restore rules from stdin
  --save            -S        save rules to stdout
  --add-server      -a        add real server with options
  --edit-server     -e        edit real server with options
  --delete-server   -d        delete real server
  --list            -L|-l     list the table
  --zero            -Z        zero counters in a service or all services
  --set tcp tcpfin udp        set connection timeout values
  --start-daemon              start connection sync daemon
  --stop-daemon               stop connection sync daemon
  --help            -h        display this help message

Options:
  --tcp-service  -t service-address   service-address is host[:port]
  --udp-service  -u service-address   service-address is host[:port]
  --fwmark-service  -f fwmark         fwmark is an integer greater than zero
  --ipv6         -6                   fwmark entry uses IPv6
  --scheduler    -s scheduler         one of rr|wrr|lc|wlc|lblc|lblcr|dh|sh|sed|nq,
                                      the default scheduler is wlc.
  --pe            engine              alternate persistence engine may be sip,
                                      not set by default.
  --persistent   -p [timeout]         persistent service
  --netmask      -M netmask           persistent granularity mask
  --real-server  -r server-address    server-address is host (and port)
  --gatewaying   -g                   gatewaying (direct routing) (default)
  --ipip         -i                   ipip encapsulation (tunneling)
  --masquerading -m                   masquerading (NAT)
  --weight       -w weight            capacity of real server
  --u-threshold  -x uthreshold        upper threshold of connections
  --l-threshold  -y lthreshold        lower threshold of connections
  --mcast-interface interface         multicast interface for connection sync
  --syncid sid                        syncid for connection sync (default=255)
  --connection   -c                   output of current IPVS connections
  --timeout                           output of timeout (tcp tcpfin udp)
  --daemon                            output of daemon information
  --stats                             output of statistics information
  --rate                              output of rate information
  --exact                             expand numbers (display exact values)
  --thresholds                        output of thresholds information
  --persistent-conn                   output of persistent connection info
  --nosort                            disable sorting output of service/server entries
  --sort                              does nothing, for backwards compatibility
  --ops          -o                   one-packet scheduling
  --numeric      -n                   numeric output of addresses and ports
  --sched-flags  -b flags             scheduler flags (comma-separated)

ipvsadm命令分为命令（Commands）和选项（Options）两部分。命令有两种形式，一个是全写，一个是缩写，功能一样，实际使用中一般缩写使用更频繁。
常用命令说明如下：

选项同样也有两种形式，一个是全写，一个是缩写，功能一致。
常用选项说明如下：

ipvsadm命令实用举例

• 添加一条虚拟服务器记录，指定加权轮询调度方式，然后指定该虚拟服务器记录添加real server，指定DR转发模式和权重

  ipvsadm -A -t 192.168.14.100:80 -s wrr
  ipvsadm -a -t 192.168.14.100:80 -r 192.168.14.129 -g -w 1
  ipvsadm -a -t 192.168.14.100:80 -r 192.168.14.130 -g -w 1

• 查看当前内核虚拟服务器表及其统计数据，“-n”参数将所有输出以数字显示

  [root@proxy ~]# ipvsadm -ln --stats
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port               Conns   InPkts  OutPkts  InBytes OutBytes
  -> RemoteAddress:Port
  TCP  192.168.14.100:80                   0        0        0        0        0
  -> 192.168.14.129:80                   0        0        0        0        0
  -> 192.168.14.130:80                   0        0        0        0        0
  [root@proxy ~]# ipvsadm -l --stats 
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port               Conns   InPkts  OutPkts  InBytes OutBytes
  -> RemoteAddress:Port
  TCP  proxy:http                          0        0        0        0        0
  -> 192.168.14.129:http                 0        0        0        0        0
  -> 192.168.14.130:http                 0        0        0        0        0

• 参数“-S”将现有ipvs规则保存输出到stdout，可重定向到配置中保存。另外，只用-S会将IP和port转义成server name和常用服务口，加 -n参数可设置数字输出

[root@proxy ~]# ipvsadm -S
-A -t proxy:http -s wrr
-a -t proxy:http -r 192.168.14.129:http -g -w 1
-a -t proxy:http -r 192.168.14.130:http -g -w 1
[root@proxy ~]# ipvsadm -Sn
-A -t 192.168.14.100:80 -s wrr
-a -t 192.168.14.100:80 -r 192.168.14.129:80 -g -w 1
-a -t 192.168.14.100:80 -r 192.168.14.130:80 -g -w 1

• -R --restore可以从stdin从恢复虚拟服务记录，和-S --save正好对应：

  [root@proxy ~]# ipvsadm -Sn > ipvs_test
  [root@proxy ~]# ipvsadm --restore < ipvs_test
  [root@proxy ~]# ipvsadm -ln
  IP Virtual Server version 1.2.1 (size=4096)
  Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
  TCP  192.168.14.100:80 wrr
  -> 192.168.14.129:80            Route   1      0          0         
  -> 192.168.14.130:80            Route   1      0          0  

ipvsadm实用总结

原文：http://blog.51cto.com/13599730/2312722