How to recover lost database .db file on FreeBSD?

sanjivkapur

sanjivkapur

Hi
I somehow deleted a few files including an important .db from trash of FreeBSD. All the while I was thinking I had the latest version backup, but now I am stuck.

I tried using FreeBSD boot up usb, using option 3, boot -s and then using grep commands to search for a string with Create command for a critical table, used dd to extract and then python and sqlite commands to recover but not successful. The red flag was I didn’t realise for 15-20 minutes and then powered it off, which seems to big issue. The FreeBSD system is using ZFS

Any help or guidance on this will be appreciated.
 
See if you have any zfs snapshots with command "zfs list -t all". You can browse all snapshots under .zfs in the zfs mounted dir. For example, if "zroot/home/rajiv" is mounted on "/home/rajiv", you can check its snapshots under "/home/rajiv/.zfs/snapshot/" dir.
 
sanjivkapur said:
I tried using FreeBSD boot up usb, using option 3, boot -s and then using grep commands to search for a string with Create command for a critical table, used dd to extract and then python and sqlite commands to recover but not successful.
Click to expand...
Nothing in FreeBSD itself depends on this. So why boot to single user mode? And what exactly are you looking for?
 
SirDice i was looking for a way to recover the sqlite database which i deleted from trash bin and did not have a current backup. so tried zfs snapshots as bakul advised, not successful. then checked for steps as per fjdlr but i do not have that option to recover.
nevertheless used another way of extracting raw data, and then restoring with a testdisk (photorec), but the db is not recoverable. so moving on, and will built it up back somehow.
 
sanjivkapur said:
mer some of my work database with tables, views, indices and triggers and data ofcourse.
Click to expand...
Well, the "of course" was not obvious to me. I think there are some uses of sqlite dbs in a default install (packages maybe a couple of others) which is why I asked.
If they were system level they could be recreated.
If they were user data (apparent now in context) then user level backup need to control.
 
sanjivkapur said:
SirDice i was looking for a way to recover the sqlite database which i deleted from trash bin and did not have a current backup. so tried zfs snapshots as bakul advised, not successful. then checked for steps as per fjdlr but i do not have that option to recover.
nevertheless used another way of extracting raw data, and then restoring with a testdisk (photorec), but the db is not recoverable. so moving on, and will built it up back somehow.
Click to expand...
Sorry to hear that. Note that zfs snapshots are quite cheap and fast. In future you may wish to snapshot frequently (may be from a cron job and another cron job to delete really old ones). Also, a good idea to backup to an external disk or machine or site (but I am sure you know that!).
 

Attachments

  • Screenshot_2026-06-26_08-17-33.png
    Screenshot_2026-06-26_08-17-33.png
    75.3 KB · Views: 8
sanjivkapur

Okay, so no BE creation and an empty .zfs directory.
You really need to make use of the extensive ZFS documentation
BE creation, snapshots, and so on.
For snapshots, you can write scripts and run them via cron, or simply install Sanoid /sysutils/sanoid/
(it's easy to configure).
ZFS offers maximum data reliability,
but you have to actually use it.
 
You must log in or register to reply here.
Back
Top