为何我做的web集群不能访问

我用三台安装Fedoral 3 内核为2.6.9的服务器做一个集群，一台做Direct ,另外两台为Realserver，三台服务器都处于同一网段. 因为下载了最新的IPVS软件（ipvsadm-1.24-6.src.rpm），下载了一个linux-2.6.16.22.tar.gz内核升级包，没有更换内核设置直接编译后将Direct Severt内核升级到2.6.16.22的内核,然后安装了IPVS,并在两台Realserver安装了Apache 2.0服务(Direct Server 没有安装，不知道需不需要)。以下是这三台服务器的配置:

1、DirectServer
[root@DirectServer ~]# ipvsadm
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.79.220:http wlc
-> 192.168.79.231:http Route 1 0 0
-> 192.168.79.230:http Route 1 0 0

[root@DirectServer ~]# sysctl -p
net.ipv4.ip_forward = 1
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
net.ipv4.tcp_syncookies = 1
[root@DirectServer network-scripts]# vi ifcfg-eth0
DEVICE=eth0
IPADDR=192.168.78.250
NETMASK=255.255.255.0
NETWORK=192.168.78.0
BROADCAST=192.168.78.255
ONBOOT=yes

[root@DirectServer network-scripts]# vi ifcfg-lo:0
DEVICE=eth0:0
BOOTPROTO=static
IPADDR=192.168.79.220
NETMASK=255.255.255.255
ONBOOT=yes

2、RealServer 1
[root@RealServer1 network-scripts]# vi ifcfg-eth0
DEVICE=eth0
BOOTPROTO=none
ONBOOT=yes
TYPE=Ethernet
IPADDR=192.168.79.230
NETMASK=255.255.248.0
BROADCAST=192.168.79.255
NETWORK=192.168.72.0
GATEWAY=192.168.72.254
[root@RealServer1 network-scripts]# vi ifcfg-lo:0
DEVICE=lo:0
BOOTPROTO=static
ONBOOT=yes
IPADDR=192.168.79.220
NETMASK=255.255.255.255
[root@RealServer1 network-scripts]# sysctl -p
net.ipv4.ip_forward = 1
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1

2、RealServer 2
[root@RealServer2 network-scripts]# vi ifcfg-eth0
DEVICE=eth0
BOOTPROTO=none
ONBOOT=yes
TYPE=Ethernet
IPADDR=192.168.79.231
NETMASK=255.255.248.0
BROADCAST=192.168.79.255
NETWORK=192.168.72.0
GATEWAY=192.168.72.254
[root@RealServer2 network-scripts]# vi ifcfg-lo:0
DEVICE=lo:0
BOOTPROTO=static
ONBOOT=yes
IPADDR=192.168.79.220
NETMASK=255.255.255.255
[root@Realserver2 ~]# sysctl -p
net.ipv4.ip_forward = 1
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_soe_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1

现在的问题是：当我在客户机（与服务器同一网段）的ＩＥ地址栏输入http://192.168.79.220时，不能打开网页，但是可以ＰＩＮＧ到这个地址，换成Realsever的地址，可以访问。进入Direct Server，用netstat查看侦听的端口，看不到TCP 80端口，不知道是什么原因，请章博士及ＬＶＳ高手指点，谢谢。