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Martin Hope
vbence
Asked: 2012-07-10 01:22:59 +0800 CST
  • 2

I have a working server with a raid > lvm > dmcrypt stack. I would like a backup solution which solves the following problems:

  • Changes only: Only transfer daily change, not the whole X Terrabytes every time. (The ability keep different versions for X days is a plus but not a must).
  • Able to restore to disk(s) with different geometry: In case of a hardware failure I can not go out and buy the exact same type of hard drives (CHS characteristics) because they will be discontinued. I can buy same or bigger size though.

The problems I see:

  • Partitions: Copying the first 512 bytes (containing the Partition table) probably won't work on disks with different geometry, So I need some intelligent partition table backup solution.
  • Raid: partitions building up the raid are marked somehow (on the last sector of the partiton manybe?). This metadata needs to be restored on the new disks (a new raid should be built). So I need a solution which can rebuild a raid identical to the old one.
  • Grub: Besides the portions of GRUB in the MBR and /boot partition I suspect there are parts stored elsewhere (unused area in first cylinder of drive maybe). So when restoring I would need some custom GRUB installer (which will install the same version).
  • dm_crypt: before restoring the data, the encrypted partitions should be set up. Of course with prompting for keys when necessary.

Restrictions by the target:

  • Samba: I only have a samba share to deposit the data, so probably some additional utility (tar) should be used to keep special file flags and ownership.
  • Encryption: File level encryption (something like encfs) should be used on the local side, because I do not want unencrypted information leave the system.
backup linux debian restore
Martin Hope
vbence
Asked: 2011-11-12 01:42:42 +0800 CST
  • 7

I use dm-crypt to encrypt partitions. I am building a small office server from consumer (or pro-sumer) category hardware. It made me wonder, hardware-assisted encryption is a notion in the air for years, is it reality yet?

The two crytical points of my question are:

  • Do the mainstream manufacturers (Asus, Gigabyte etc.) ship products with these (cheap) chips?
  • Does the Linux kernel have a (reasonably old) implementation for the hardware and integration with dm-crypt?

Bonus: The same two question with TPM chips. Do manufacturers integrate them to their hardware already? Are they supported by Linux? Do they speed anything up? Do they have any performance advantage?

linux debian encryption disk-encryption
Martin Hope
vbence
Asked: 2011-05-21 00:44:45 +0800 CST
  • 1

I'm looking for a guide, or just a list of tools with some advice. I want to protect the emails stored on the server-side (in a Courier-IMAP server).

A basic flowchart to illustrate the idea.

 [Unencrypted mail comes in]
              |
 [Encryption with public key]
              |
      [Saved to file]
              |
   [Client downloads file]
              |
[Decryption with private key]

I use Thunderbird. I am sure it can be done, it's a pretty streightforward process. May be an other program should be inseted between the mail client and the server, or an extension has to be used. May be the original message file has to be an attachment to a wrapper message (to be flawlessly handleled by the mail client). May be an add-on can help.

I'm open to any ideas how to solve this.

encryption imap