因為測試的 CentOS 7 是在家裡使用，所以 IPv6 應該是使用不到的
# ifconfig eth0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.109 netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::20c:29ff:fea6:2215 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:a6:22:15 txqueuelen 1000 (Ethernet)
RX packets 462 bytes 41942 (40.9 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 356 bytes 46939 (45.8 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
[@more@]修改方式
修改 /etc/default/grub
在 GRUB_CMDLINE_LINUX 後加上 ipv6.disable=1
# vim /etc/default/grub
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=”$(sed ‘s, release .*$,,g’ /etc/system-release)”
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL_OUTPUT=”console”
GRUB_CMDLINE_LINUX=”rd.lvm.lv=centos/swap vconsole.font=latarcyrheb-sun16 rd.lvm.lv=centos/root crashkernel=auto vconsole.keymap=us rhgb quiet net.ifnames=0 biosdevname=0 ipv6.disable=1“
GRUB_DISABLE_RECOVERY=”true”
產生新的 grub 設定檔
# grub2-mkconfig -o /boot/grub2/grub.cfg
Generating grub configuration file …
Found linux image: /boot/vmlinuz-3.10.0-123.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-123.el7.x86_64.img
Warning: Please don’t use old title `CentOS Linux, with Linux 3.10.0-123.el7.x86_64′ for GRUB_DEFAULT, use `Advanced options for CentOS Linux>CentOS Linux, with Linux 3.10.0-123.el7.x86_64′ (for versions before 2.00) or `gnulinux-advanced-caeda11c-71b9-4cc4-961b-b4541b247804>gnulinux-3.10.0-123.el7.x86_64-advanced-caeda11c-71b9-4cc4-961b-b4541b247804′ (for 2.00 or later)
Found linux image: /boot/vmlinuz-0-rescue-07f9be0c0fc843ce885a7539150c8e55
Found initrd image: /boot/initramfs-0-rescue-07f9be0c0fc843ce885a7539150c8e55.img
done
重新開機
# sync;sync;sync;sync;shutdown -r
IPv6 已經關閉
# ifconfig eth0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.109 netmask 255.255.255.0 broadcast 192.168.1.255
ether 00:0c:29:a6:22:15 txqueuelen 1000 (Ethernet)
RX packets 83 bytes 8436 (8.2 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 73 bytes 10238 (9.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0