Are purged messages wiped from the hard drive?

[ThorGoLucky]

Hi, I showed Zimbra to my bosses and one of the questions they had was whether purged mail was truly purged (wiped/overwritten) from the hard drives.

By "purging", I mean both the system-wide automatic purge and a user emptying their trash.

Thanks.

[dkarp]

When messages are "hard deleted" (nightly purge, empty spam/trash folder), they are permanently gone from that user's mailbox. Each message is stored as a single file on disk, so deleting mail from the system is the same as a normal Linux/Mac file delete.

[ThorGoLucky]

Thanks for your prompt response. What do you mean by "Hard Delete"? Is this equivalent to a "wipe"? Does this mean that it is impossible to recover the email even with special programs? Thanks.

[dkarp]

It means that the file is deleted like any other UNIX file is deleted, but no other "wiping" is performed.

[ThorGoLucky]

I found the following at http://batleth.sapienti-sat.org/proj.../ext3-faq.html

Q: How can I recover (undelete) deleted files from my ext3 partition?
Actually, you can't! This is what one of the developers, Andreas Dilger, said about it:

In order to ensure that ext3 can safely resume an unlink after a crash, it actually zeros out the block pointers in the inode, whereas
ext2 just marks these blocks as unused in the block bitmaps and marks the inode as "deleted" and leaves the block pointers alone.

I'm using the ext3 filesystem under Red Hat EL 4 64-bit, so it looks like I don't need to worry about deleted emails hanging around.

[dijichi2]

this implies the data still exists, just the references are deleted.

[jholder]

Trust me, if you have ext3, and you delete it, there's no way to recover it.

You can on ext2 tho, assumng the inodes arn't overwritten.