lvs/tun+ha+ldirectord

[wlx]

ldirectord can't monitor realserver's tunnel?my cluster obtain 4 realservers with squid,i found when a realserver's (eg:192.168.100.120)tunnel is down,then run ipvsadm -ln :
[root at backup mon-1.1.0pre1]# ipvsadm -ln
IP Virtual Server version 1.2.0 (size=1048576)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.100.203:80 wlc
  -> 192.168.100.128:80          tunnel  1      0          0         
  -> 192.168.100.120:80          tunnel  1     0          0         
  -> 192.168.100.125:80         tunnel 1      0          0    

all seem ok,but when i run  #>telnet 192.168.100.203 80
正在连接到192.168.100.203...不能打开到主机的连接， 在端口 80: 连接失败   
why?
who can help me? thanks