Linux更改machine ID

用systemd-machine-id-setup可以重新生成machine ID。

如果DBUS machine ID存在的话，会直接将其拷贝过来，所以可以先更新DBUS machine ID：

sudo bash -c "dbus-uuidgen > /var/lib/dbus/machine-id"
sudo rm /etc/machine-id
sudo systemd-machine-id-setup

Initializing machine ID from D-Bus machine ID.

参考: https://www.linuxquestions.org/questions/slackware-14/security-implications-of-var-lib-dbus-machine-id-thoughts-4175665203/

也可以把/var/lib/dbus/machine-id和/etc/machine-id一起删除，再用systemd-machine-id-setup重新生成/etc/machine-id，然后再创建一个符号链接：

sudo rm /var/lib/dbus/machine-id /etc/machine-id
sudo systemd-machine-id-setup
sudo ln -s /etc/machine-id /var/lib/dbus/machine-id

ArchLinux的/var/lib/dbus/machine-id默认就是一个指向/etc/machine-id的符号链接。

参考：

Linux7重新生成Machine-ID

https://wiki.debian.org/MachineId