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Yes but isolated registry backups make as much sense as a full backup of a modern Linux Desktop's /etc folder. Probably not much. The config's content depends a

Yes but isolated registry backups make as much sense as a full backup of a modern Linux Desktop's /etc folder. Probably not much. The config's content depends a lot on the things installed and vice-versa, even more so on Windows (unless they changed something fundamentally since 7). At least on Linux and in particular Ubuntu (Desktop) installations I aim for as little manual configuration changes as possible anyways, so updates don't break things...

outworlder 7y ago
If you backup etc and home, you can pretty much restore a linux machine back to working order. Yes, you might be missing packages in a brand new install, but then the extra files are harmless. People put etc in git even: https://joeyh.name/code/etckeeper/ https://joeyh.name/code/etckeeper/ The registry is much more magical and it is difficult to find and remove cruft, so I suppose there's an argument against it.
- la_barba 7y ago
  >If you backup etc and home, you can pretty much restore a linux machine back to working order. Hmm, I've never done this. In terms of config files, are there never any breaking changes between versions? Like ..is a v1.0 config file always guaranteed to work with v2.0 and vice versa? I guess and a related question - what is the best way to determine if an /etc/ config file isn't required?
  - velosol 7y ago
    Usually breaking changes are highlighted in your update cycle and if something is added or slightly modified you might find a *.conf.rpmnew or similar. rpmconf [1] helps with those sorts of updates. [1]: https://github.com/xsuchy/rpmconf https://github.com/xsuchy/rpmconf
  - rincebrain 7y ago
    Stuff can break - there's not especially strong guarantees across versions, but if I, say, took /etc and /home from a Debian stretch system and put them on another Debian system, it would likely mostly Just Work. It gets more exciting the further you drift - e.g. if you're going to Debian buster, or something more significantly different like Fedora/RH, you'd probably want to cherrypick config changes from /etc, though /home should be fine(tm).
  - pas 7y ago
    etckeeper records the exact package version changes too. it's extremely handy for small shops (so unless you do 100% immutable infrastructure, it's worth it) you start culling packages with apt purge, that should remove config files too, and see what breaks, if nothing, well, try to push your luck further. also with dpkg -S /etc/some/file you can see which file belongs to which package and target that package usually on a server you know what you don't need. it's a bit more trial and error on a desktop. (because those can break in a lot more fun, unexpected ways, harder to know what is needed)
- zaarn 7y ago
  There are more reasons than backups to use etckeeper; I use it in case a package upgrade mangles my config files (happened once). Imagine the use case in reality. You accidentally rm -rf your /etc folder but you still have the git tree. /etc itself is gone, entirely. Most of your tools will seize working almost immediately, the only chances you have are having a terminal already open to a root shell. Your Virtual TTYs on other screens won't work (login uses /etc/passwd, which is gone) as well as any sudo command. Recovery from the life system is likely impossible unless you have a root shell open and git doesn't refuse to work (it might since it checks for /etc/gitconfig, if you made any critical settings here, git stops working). Live recovery also has other issue; some apps might still be writing to or reading from /etc. They might have an open handle. Recovery will result in some processes of the same binary running with different configurations. That will be a joy to discover once it inevitably starts to corrupt the system stability. So your only way of meaningful recovery is a live system on a USB stick. Do you have one ready to use right now? Like, not prepared in a shelf somewhere but right now is there a live linux system within your reach? If not, it's rather likely it will take a while to find it. Once you've done that, you can bootup your computer, unlock any encrypted disks you use and install git into the live system. Then you hopefully remember how to recover a git repo using it's tree only, if not, hopefully the live disk's network works. If recovery succeeds over git, you can reboot and pray the last checkpoint in git isn't too old. Have you changed the LUKS keys in the meantime and did you forget to checkin crypttab? Or did you change your Xorg Conf because X stopped working? The short answer is; it might be easier and just as complex to simply reinstall the system while backing up your home folder.
marcosdumay 7y ago
Well, the backups of /etc on my home server helped me many times. I would advise anybody to do them.
Causality1 7y ago
Isolated registry backups are handy if you do a lot of poking around in the registry by hand or if you're about to install a .reg file. Regardless, the dialog box actively lying to the user is what's completely unacceptable.
jlg23 7y ago
But config not being read by things not installed does not hurt either. And once I install these missing things, the config is read again. And I usually spend a lot more time with configuration than with installing...
microwavecamera 7y ago
There's a key difference though. In Linux and other UNIX inspired OS's /etc is only accessible by root but the Windows registry holds config data for users too. Any userspace program in Windows could potentially bork any registry key that the user has access too.

outworlder 7y ago

If you backup etc and home, you can pretty much restore a linux machine back to working order. Yes, you might be missing packages in a brand new install, but then the extra files are harmless. People put etc in git even: https://joeyh.name/code/etckeeper/ https://joeyh.name/code/etckeeper/ The registry is much more magical and it is difficult to find and remove cruft, so I suppose there's an argument against it.

la_barba 7y ago
>If you backup etc and home, you can pretty much restore a linux machine back to working order. Hmm, I've never done this. In terms of config files, are there never any breaking changes between versions? Like ..is a v1.0 config file always guaranteed to work with v2.0 and vice versa? I guess and a related question - what is the best way to determine if an /etc/ config file isn't required?
- velosol 7y ago
  Usually breaking changes are highlighted in your update cycle and if something is added or slightly modified you might find a *.conf.rpmnew or similar. rpmconf [1] helps with those sorts of updates. [1]: https://github.com/xsuchy/rpmconf https://github.com/xsuchy/rpmconf
- rincebrain 7y ago
  Stuff can break - there's not especially strong guarantees across versions, but if I, say, took /etc and /home from a Debian stretch system and put them on another Debian system, it would likely mostly Just Work. It gets more exciting the further you drift - e.g. if you're going to Debian buster, or something more significantly different like Fedora/RH, you'd probably want to cherrypick config changes from /etc, though /home should be fine(tm).
- pas 7y ago
  etckeeper records the exact package version changes too. it's extremely handy for small shops (so unless you do 100% immutable infrastructure, it's worth it) you start culling packages with apt purge, that should remove config files too, and see what breaks, if nothing, well, try to push your luck further. also with dpkg -S /etc/some/file you can see which file belongs to which package and target that package usually on a server you know what you don't need. it's a bit more trial and error on a desktop. (because those can break in a lot more fun, unexpected ways, harder to know what is needed)
zaarn 7y ago
There are more reasons than backups to use etckeeper; I use it in case a package upgrade mangles my config files (happened once). Imagine the use case in reality. You accidentally rm -rf your /etc folder but you still have the git tree. /etc itself is gone, entirely. Most of your tools will seize working almost immediately, the only chances you have are having a terminal already open to a root shell. Your Virtual TTYs on other screens won't work (login uses /etc/passwd, which is gone) as well as any sudo command. Recovery from the life system is likely impossible unless you have a root shell open and git doesn't refuse to work (it might since it checks for /etc/gitconfig, if you made any critical settings here, git stops working). Live recovery also has other issue; some apps might still be writing to or reading from /etc. They might have an open handle. Recovery will result in some processes of the same binary running with different configurations. That will be a joy to discover once it inevitably starts to corrupt the system stability. So your only way of meaningful recovery is a live system on a USB stick. Do you have one ready to use right now? Like, not prepared in a shelf somewhere but right now is there a live linux system within your reach? If not, it's rather likely it will take a while to find it. Once you've done that, you can bootup your computer, unlock any encrypted disks you use and install git into the live system. Then you hopefully remember how to recover a git repo using it's tree only, if not, hopefully the live disk's network works. If recovery succeeds over git, you can reboot and pray the last checkpoint in git isn't too old. Have you changed the LUKS keys in the meantime and did you forget to checkin crypttab? Or did you change your Xorg Conf because X stopped working? The short answer is; it might be easier and just as complex to simply reinstall the system while backing up your home folder.

marcosdumay 7y ago

Well, the backups of /etc on my home server helped me many times. I would advise anybody to do them.

Causality1 7y ago

Isolated registry backups are handy if you do a lot of poking around in the registry by hand or if you're about to install a .reg file. Regardless, the dialog box actively lying to the user is what's completely unacceptable.

jlg23 7y ago

But config not being read by things not installed does not hurt either. And once I install these missing things, the config is read again. And I usually spend a lot more time with configuration than with installing...

microwavecamera 7y ago

There's a key difference though. In Linux and other UNIX inspired OS's /etc is only accessible by root but the Windows registry holds config data for users too. Any userspace program in Windows could potentially bork any registry key that the user has access too.