traceroute 结果中的！A ！H是什么意思？

doofy

新手学TCP/IP
跟踪了下到www.baidu.com 路由  
$traceroute  202.108.22.43
1  192.168.10.1 (192.168.10.1)  1.437 ms  1.312 ms  0.508 ms
2  172.30.67.29 (172.30.67.29)  2.431 ms  2.118 ms  2.010 ms
3  10.255.56.9 (10.255.56.9)  5.008 ms  3.089 ms  1.702 ms
4  218.241.239.32 (218.241.239.32)  2.508 ms  3.987 ms  3.291 ms
5  210.75.97.193 (210.75.97.193)  3.917 ms  3.717 ms  1.549 ms
6  202.99.57.149 (202.99.57.149)  2.988 ms  2.785 ms  3.233 ms
7  202.106.102.225 (202.106.102.225)  3.702 ms  3.881 ms  4.757 ms
8  202.96.13.129 (202.96.13.129)  5.020 ms  2.886 ms  2.734 ms
9  202.106.192.157 (202.106.192.157)  2.386 ms  3.460 ms  3.974 ms
10  61.148.3.58 (61.148.3.58 )  3.239 ms  4.248 ms  3.580 ms
11  * 202.106.48.18 (202.106.48.18 )  3.746 ms !A  2.954 ms !A
$
!A 是什么意思？
并且TTL 2 3 路由明显异常 应该属于保留ip
然后 tracerouter了下网关的外网ip
$ cat tr_gw
1  192.168.10.1 (192.168.10.1)  3.350 ms  0.599 ms  0.532 ms
2  * * *
3  192.168.10.1 (192.168.10.1)  233.763 ms !H * *
这！H又是啥意思呢

望高手带带~~

[ 本帖最后由 doofy 于 2007-8-22 18:06 编辑 ]

sungkung

A
Administratively prohibited (example, access-list)
H
Host unreachable