Re: [gentoo-user] {OT} Are "push" backups flawed?

[Grant]

>>>>> And if I pull, none of my backed-up systems are secure because anyone
>>>>> who breaks into the backup server has root read privileges on every
>>>>> backed-up system and will thereby "gain full root privileges quickly."
>>>>
>>>> IMO that depends on whether you also backup the authentication-related
>>>> files or not. Exclude them from backup, ensure different root passwords
>>>> for all boxes, and now you can limit the infiltration.
>>>
>>> If you're pulling to the backup server, that backup server has to be
>>> able to log in to and read all files on the other servers. Including
>>> e.g. your swap partition and device files.
>>
>> What if I have each system save a copy of everything to be backed up
>> from its own filesystem in a separate directory and change the
>> ownership of everything in that directory so it can be read by an
>> unprivileged backup user?
>
> You've just reinvented the push backup =)
>
> If separate-directory is on the same server, an attacker can log in and
> overwrite all of your files with zeros. Those zeros will be pulled to
> the backup server, destroying your backups.

That's not the case at all.  The zeros would be pulled to the backup
server via rdiff-backup and saved as a new version in the repository.
The backups would be safe.

- Grant


> If separate-directory is on the backup server...