11 Replies to “Tarsnap talk on-line”

  1. Excellent talk!

    I didn’t quite follow the bit where you talked about compressing a text file (or not).

    To take advantage of the compression and deduplication, should one avoide uploading compressed files (if possible)?

    For example, I backup my ZFS system to a file and then compress it so I have files called: 2015.05.01.zfs.gz, 2015.05.02.zfs.gz, etc. Is it a bad idea to upload files like this to Tarsnap? I assume compression won’t help here but can dedupe help?

  2. SW,

    ZFS filesystem-level compression is a different beast. Tarsnap dedup works fine if your dataset has compress=lz4 or somesuch. The filesystem presents the decompressed file, and Tarsnap can dedup that just fine.

    Deduplication has problems when you run, say, “gzip mysqlbackup.sql” — two different database dumps might be 99% identical, but compressing at the file level creates a completely different dump.gz files.

  3. I’ve just finished reading Tarsnap Mastery, it was a fantastic read! Then again, all your books are fantastic.

    Despite everything I read in the Tarsnap book, would you trust Tarsnap with your backups that include password information? ie: login credentials etc. I’m one of those ultra paranoid people that doesn’t use ANY cloud service and keeps everything on my own desktop/server at home. Having said that I am close to starting to use Tarsnap…

    On another note, will you be writing a mastery book on Jails?

    Oh, can’t wait for the Advanced ZFS Mastery book to come out, the first one was awesome!!

  4. Mr. Lucas,

    Thanks for tarsnap mastery and all your other non-fiction books, of which I own all but 3 or 4.

    Keep up the great works of authoring and I’ll keep buying!


  5. If I use an encrypted key (ie: with a passphrase) with tarsnap, I assume that when I print out the key file for my backups that I use the encrypted key and NOT the unencrypted (ie: no password) one?

    I know this sounds dumb but I thought I’d make sure!!

  6. Up to you, Paul.

    For me, if I need to keep my Tarsnap keys in a safe deposit box, I’d probably print both. Because if I’m using that key, my business is fubar without the key.

    You might ask on the tarsnap-users mailing list for other opinions, though.

Comments are closed.