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I'm planning to use rsnapshot to backup a veracrypt volume as it changes.
This means I will have multiple versions of the same volume, with slight differences in data.
It is my understanding that this makes certain analysis attacks easier, and that certain ciphers and encryption algorithms can protect better against this specific problem.
With that in mind, what options would be best to configure a new veracrypt volume with?
Making snapshots of encrypted disks non-diff based is problematic as the view on the encrypted data is just "one big ball of garbage", e.g. there isn't even a valid file system.
How much actually changes depends on the mode of operation the bloch cipher in question is used in.
If (which is the default, AFAIK) you are using the GCM, the actual changes to the data are kept to a reasonable minimum, but diff'ing huge binary is not ideal either.
Hence, you may want to rethink that. Maybe making snapshots of the decrypted file system on another encrypted disk is an option, depending on your situation / what you actually want to achieve.
Please also note that modern ciphers are not vulnerable to Ciphertext only attacks, which is basically what you have in mind regarding the security of your planned system.
