В США испугались стремительной потери союзников из-за Ирана08:22
Contrary to how some other immutable Linux operating systems handle /etc, it is not a read-only overlay with a writable layer on top. Instead, /usr ships a set of default config files, and systemd-tmpfiles creates symlinks from /etc back into /usr on first boot. This means that if you haven't touched a config file, it automatically reflects whatever the current image provides. Booting an older image gives you older defaults. If you want to customize something, you copy the file out of the factory in /usr into /etc, breaking the symlink, and then edit it. Your changes persist across updates. More details on this are available on the wiki.
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