redhat上ipv4可以ping通，ipv6ping不通？？？

[沈万三gz]

RT.在线求助。

[root@Centos6x64 ~]# ifconfig -a
eth1      Link encap:Ethernet  HWaddr 00:50:56:B7:74:0B  
          inet addr:192.168.200.185  Bcast:192.168.203.255  Mask:255.255.252.0
          inet6 addr: fe80::250:56ff:feb7:740b/64 Scope:Link
          inet6 addr: 2002:c0a8:c8b9::50:56b7:740b/16 Scope:Global
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:13455 errors:0 dropped:0 overruns:0 frame:0
          TX packets:323 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:1113343 (1.0 MiB)  TX bytes:39192 (38.2 KiB)
 
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:995436 errors:0 dropped:0 overruns:0 frame:0
          TX packets:995436 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:439491502 (419.1 MiB)  TX bytes:439491502 (419.1 MiB)
 
sit0      Link encap:IPv6-in-IPv4  
          NOARP  MTU:1480  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

[root@Centos6x64 ~]# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.200.0   *               255.255.252.0   U     0      0        0 eth1
link-local      *               255.255.0.0     U     1002   0        0 eth1
default         192.168.200.1   0.0.0.0         UG    0      0        0 eth1