标签：style blog http color 使用 os io for
英语学得不好，国外这位大神的精彩解释不是特能看的懂。我模仿的试了一下。
解决方案：
1.打开mac终端
2.输入：sudo ifconfig lo0 alias 127.1.1.1 netmask 0xFFFFFFFF
3.浏览器测试。
（如果是127.0.0.2）应该就是：sudo ifconfig lo0 alias 127.0.0.2 netmask 0xFFFFFFFF
大神给予的解释：
FreeBSD (also OS X, and I believe NetBSD & OpenBSD) will respond to requests sent to configuredaddresses on the loopback interface, just as they would for addresses on any other interface -- If you want an answer you need to assign the address first:
mgraziano@monitor ~]$ ifconfig lo0
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
options=3<RXCSUM,TXCSUM>
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3
inet6 ::1 prefixlen 128
inet 127.0.0.1 netmask 0xff000000
nd6 options=3<PERFORMNUD,ACCEPT_RTADV>
[mgraziano@monitor ~]$ ping 127.1.1.1
PING 127.1.1.1 (127.1.1.1): 56 data bytes
ping: sendto: Can‘t assign requested address
^C
[mgraziano@monitor ~]$ sudo ifconfig lo0 alias 127.1.1.1 netmask 0xFFFFFFFF
[mgraziano@monitor ~]$ ifconfig lo0
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
options=3<RXCSUM,TXCSUM>
inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3
inet6 ::1 prefixlen 128
inet 127.0.0.1 netmask 0xff000000
inet 127.1.1.1 netmask 0xffffffff
nd6 options=3<PERFORMNUD,ACCEPT_RTADV>
[mgraziano@monitor ~]$ ping 127.1.1.1
PING 127.1.1.1 (127.1.1.1): 56 data bytes
64 bytes from 127.1.1.1: icmp_seq=0 ttl=64 time=0.020 ms
^C
On the logic behind this implementation, see RFC 3330:
127.0.0.0/8 - This block is assigned for use as the Internet host
loopback address. A datagram sent by a higher level protocol to an
address anywhere within this block should loop back inside the host.
This is ordinarily implemented using only 127.0.0.1/32 for loopback,
but no addresses within this block should ever appear on any network
anywhere [RFC1700, page 5].
来自国外：http://serverfault.com/questions/293874/why-cant-i-ping-an-address-on-the-loopback-device-under-freebsd
mac系统不能使用127.0.0.2的解决方案,布布扣,bubuko.com
标签：style blog http color 使用 os io for
原文地址：http://www.cnblogs.com/chenshuo/p/3875253.html
