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特殊MAC地址---官方保留

IEEE Std 802.1D and IEEE Std 802.1Q Reserved Addresses Group MAC address value Organization
using the value
Standard using the value Notes 01-80-C2-00-00-00 IEEE 802 IEEE Std 802.1D
IEEE Std 802.1Q IEEE Std 802.1D Bridge Group Address 01-80-C2-00-00-01 IEEE 802 " IEEE MAC-specific control protocols 01-80-C2-00-00-02 IEEE 802 " IEEE Std 802.3 Slow Protocols multicast address 01-80-C2-00-00-03 IEEE 802 " IEEE Std 802.1X PAE address 01-80-C2-00-00-04 IEEE 802 " IEEE MAC-specific control protocols 01-80-C2-00-00-05 IEEE 802 " Reserved for media access method specific use 01-80-C2-00-00-06 IEEE 802 " Reserved for future standardization 01-80-C2-00-00-07 IEEE 802 " Reserved for future standardization 01-80-C2-00-00-08 IEEE 802 " Provider Bridge group address 01-80-C2-00-00-09 IEEE 802 " Reserved for future standardization 01-80-C2-00-00-0A IEEE 802 " Reserved for future standardization 01-80-C2-00-00-0B IEEE 802 " Reserved for future standard…

Raspberri-Pi Debian Tuning

Speedup CPU:
we can easily modify the cpu work frequency modifying the config.txt file. Just edit /boot/config.txt
arm_freq=900
i always use this hack and my rpi run without problem
Change scheduler/elevator at boot time:
we use more responsive/less disk io usage scheduler:
modify the /boot/cmdline.txt 
dwc_otg.lpm_enable=0 root=/dev/mmcblk0p2 rootfstype=ext4 rootflags=commit=120,data=writeback elevator=deadline rootwait quiet
Tuning sysctl.conf:
as manual say, sysctl.conf is the “Configuration file for setting system variables”... well there are lot of variables you can put inside this file and for everyone we can write a book.
Our goal is to gain more speed and tell our system to use less io/ram. Let’s put in the /etc/sysctl.conf:
vm.dirty_background_ratio = 20
vm.dirty_expire_centisecs = 0
vm.dirty_ratio = 80
vm.dirty_writeback_centisecs = 1200
vm.overcommit_ratio = 2
vm.laptop_mode = 5
vm.swappiness = 10
Removing unused services:
Removing services is a must to do for every system or computer, i have…