关于Linux和Windows中的MTU
红色为命令和注释、修改后的MTU，蓝色的为修改前的MTU
Linux中设置MTU值的三种方法：
[[email protected] ~]# ifconfig //查看网卡信息
eth0 Link encap:Ethernet HWaddr 00:0C:29:0C:B8:6A
inet addr:192.168.10.1 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe0c:b86a/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1948 errors:0 dropped:0 overruns:0 frame:0
TX packets:87 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:208651 (203.7 KiB) TX bytes:17782 (17.3 KiB)
Interrupt:169 Base address:0x2000
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:7442 errors:0 dropped:0 overruns:0 frame:0
TX packets:7442 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:9177752 (8.7 MiB) TX bytes:9177752 (8.7 MiB)
第一种：
[[email protected] ~]# ifconfig eth0 mtu 1492
eth0 Link encap:Ethernet HWaddr 00:0C:29:0C:B8:6A
inet addr:192.168.10.1 Bcast:192.168.10.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe0c:b86a/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1492 Metric:1
RX packets:1948 errors:0 dropped:0 overruns:0 frame:0
TX packets:87 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:208651 (203.7 KiB) TX bytes:17782 (17.3 KiB)
Interrupt:169 Base address:0x2000
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:7442 errors:0 dropped:0 overruns:0 frame:0
TX packets:7442 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:9177752 (8.7 MiB) TX bytes:9177752 (8.7 MiB)
[[email protected] ~]#
第二种方法：
[[email protected] ~]# ip link list
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
link/ether 00:0c:29:0c:b8:6a brd ff:ff:ff:ff:ff:ff
3: sit0: <NOARP> mtu 1480 qdisc noop
link/sit 0.0.0.0 brd 0.0.0.0
[[email protected] ~]# ip link set dev eth0 mtu 1492
[[email protected] ~]# ip link list
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1492 qdisc pfifo_fast
qlen 1000
link/ether 00:0c:29:0c:b8:6a brd ff:ff:ff:ff:ff:ff
3: sit0: <NOARP> mtu 1480 qdisc noop
link/sit 0.0.0.0 brd 0.0.0.0
[[email protected] ~]#
第三种方法：
[[email protected] ~]# vi /etc/sysconfig/network-scripts/ifcfg-eth0
[[email protected] ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]
DEVICE=eth0
BOOTPROTO=none
HWADDR=00:0C:29:0C:B8:6A
ONBOOT=yes
NETMASK=255.255.255.0
IPADDR=192.168.10.1
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes
[[email protected] ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
# Advanced Micro Devices [AMD] 79c970 [PCnet32 LANCE]
DEVICE=eth0
MTU=1492
BOOTPROTO=none
HWADDR=00:0C:29:0C:B8:6A
ONBOOT=yes
NETMASK=255.255.255.0
IPADDR=192.168.10.1
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes
[[email protected] ~]#
最后重启网络服务
[[email protected] ~]#service network restart eth0
Windows xp\vista\win 7中测试MTU
修改注册表中以下这项，
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services \Tcpip\Parameters\Interfaces\
在这项下有几个网卡信息，你点击每个看右边IPAddress项，对应自己网卡IP的就是的再输入数值。
至于为什么Windows中MTU是1492，是因为我的是ADSL拨号(pppoe)上网的，不是1492可能有些网页无法游览。MTU最大值在以太网帧中是1500字节。
转载于:https://blog.51cto.com/kennywong/247664