solaris高手请帮忙解决下 ping IP和域名的问题!!

我的solaris 10 下的一台DNS服务器
resolv.conf文件内容如下:
domain ooo.com
nameserver 127.0.0.1
nameserver 202.103.96.68

nsswitch.conf文件内容如下
passwd:     files
group:      files
hosts:      files dns
ipnodes:    files
networks:   files
.....

我在服务器上
# nslookup www.163.com
Server:         127.0.0.1
Address:        127.0.0.1#53

Non-authoritative answer:
www.163.com     canonical name = www.cache.split.netease.com.
Name:   www.cache.split.netease.com 网管u家u.bitsCN.com
Address: 220.181.28.50
Name:   www.cache.split.netease.com
Address: 220.181.28.51
Name:   www.cache.split.netease.com
Address: 220.181.28.52
Name:   www.cache.split.netease.com
Address: 220.181.28.53
Name:   www.cache.split.netease.com
Address: 220.181.28.54
域名解析正常

ping 域名也没有问题
# ping -s www.sina.com.cn
PING www.sina.com.cn: 56 data bytes
64 bytes from 58.63.236.50: icmp_seq=0. time=16.4 ms
64 bytes from 58.63.236.50: icmp_seq=1. time=16.0 ms
64 bytes from 58.63.236.50: icmp_seq=2. time=16.0 ms
64 bytes from 58.63.236.50: icmp_seq=3. time=16.0 ms
64 bytes from 58.63.236.50: icmp_seq=4. time=16.0 ms
64 bytes from 58.63.236.50: icmp_seq=5. time=16.1 ms
64 bytes from 58.63.236.50: icmp_seq=6. time=16.2 ms

但是ping ip地址有问题了,
# ping -s 202.103.86.3
PING 202.103.86.3: 56 data bytes
64 bytes from 202.103.86.3: icmp_seq=0. time=8.44 ms
64 bytes from 202.103.86.3: icmp_seq=1. time=1.00e+05 ms
64 bytes from 202.103.86.3: icmp_seq=2. time=9.92e+04 ms
64 bytes from 202.103.86.3: icmp_seq=3. time=9.82e+04 ms
64 bytes from 202.103.86.3: icmp_seq=4. time=9.72e+04 ms
64 bytes from 202.103.86.3: icmp_seq=5. time=9.62e+04 ms
64 bytes from 202.103.86.3: icmp_seq=6. time=9.52e+04 ms
64 bytes from 202.103.86.3: icmp_seq=7. time=9.42e+04 ms
64 bytes from 202.103.86.3: icmp_seq=8. time=9.32e+04 ms
64 bytes from 202.103.86.3: icmp_seq=9. time=9.22e+04 ms 中国网管论坛bbs.bitsCN.com
64 bytes from 202.103.86.3: icmp_seq=10. time=9.12e+04 ms
64 bytes from 202.103.86.3: icmp_seq=11. time=8.01 ms
64 bytes from 202.103.86.3: icmp_seq=12. time=7.98 ms
......
可见前面1-到10次ping出现e+的情况,然后又正常了,请问这是什么原因?怎么解决这样的问题?


如果修改nsswitch.conf文件,去掉file dns 后的dns
则ping域名不通
# ping -s www.163.com
ping: unknown host www.163.com
# ping www.sina.com.cn
ping: unknown host www.sina.com.cn

pingIP地址又正常了
 # ping -s 202.103.86.3
PING 202.103.86.3: 56 data bytes
64 bytes from 202.103.86.3: icmp_seq=0. time=8.48 ms
64 bytes from 202.103.86.3: icmp_seq=1. time=8.11 ms

网管联盟bitsCN_com

64 bytes from 202.103.86.3: icmp_seq=2. time=7.95 ms
64 bytes from 202.103.86.3: icmp_seq=3. time=8.06 ms
64 bytes from 202.103.86.3: icmp_seq=4. time=8.17 ms
64 bytes from 202.103.86.3: icmp_seq=5. time=8.02 ms
64 bytes from 202.103.86.3: icmp_seq=6. time=8.00 ms
64 bytes from 202.103.86.3: icmp_seq=7. time=8.10 ms
64 bytes from 202.103.86.3: icmp_seq=8. time=8.08 ms
64 bytes from 202.103.86.3: icmp_seq=9. time=8.06 ms
64 bytes from 202.103.86.3: icmp_seq=10. time=8.02 ms
64 bytes from 202.103.86.3: icmp_seq=11. time=8.00 ms
64 bytes from 202.103.86.3: icmp_seq=12. time=7.98 ms
64 bytes from 202.103.86.3: icmp_seq=13. time=8.09 ms
.....

难道solaris里的ping机制受nsswitch.conf里的dns影响吗?加了dns项之后
还会去寻找dns做反向解析吗?我只知道telnet,ssh受dns的反向解析影响,请问各位高手,
我想能在服务器上既能正常ping IP 地址又能正常ping域名,请高手帮忙解决!谢谢