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I have a very old wallet.dat that I've put into my .bitcoin folder. When trying to run bitcoind, the service stops giving the following error

2019-06-11T18:14:02Z Using wallet directory /home/nom/.bitcoin
2019-06-11T18:14:02Z init message: Verifying wallet(s)...
2019-06-11T18:14:02Z Using BerkeleyDB version Berkeley DB 4.8.30: (April  9, 2010)
2019-06-11T18:14:02Z Using wallet wallet.dat
2019-06-11T18:14:02Z BerkeleyEnvironment::Open: LogDir=/home/nom/.bitcoin/database ErrorFile=/home/nom/.bitcoin/db.log
2019-06-11T18:14:02Z Renamed wallet.dat to wallet.dat.1560276842.bak
2019-06-11T18:14:02Z BerkeleyEnvironment::Salvage: Database salvage found errors, all data may not be recoverable.
2019-06-11T18:14:02Z BerkeleyEnvironment::Salvage: WARNING: Unexpected end of file while reading salvage output.
2019-06-11T18:14:02Z Salvage(aggressive) found no records in wallet.dat.1560276842.bak.
2019-06-11T18:14:02Z Error: wallet.dat corrupt, salvage failed
Error: wallet.dat corrupt, salvage failed
2019-06-11T18:14:02Z Shutdown: In progress...

Edit. Here is the content of the DB log

file unknown has LSN 1/151495, past end of log at 1/28 Commonly caused by moving a database from one database environment to another without clearing the database LSNs, or by removing all of the log files from a database environment Page 0: metadata page corrupted Page 0: could not check metadata page wallet.dat: DB_VERIFY_BAD: Database verification failed file unknown has LSN 1/151495, past end of log at 1/1080 Commonly caused by moving a database from one database environment to another without clearing the database LSNs, or by removing all of the log files from a database environment wallet.dat.1560341204.bak: DB_VERIFY_BAD: Database verification failed file unknown has LSN 1/151495, past end of log at 1/2500 Commonly caused by moving a database from one database environment to another without clearing the database LSNs, or by removing all of the log files from a database environment wallet.dat.1560341352.bak: DB_VERIFY_BAD: Database verification failed

Edit. Using db_dump I am able to see the content of the wallet file ( addresses, keys etc)

Is there any way I could debug this, perhaps recovering just part of the keys or any useful data from the DB itself? Any useful hints how to approach such recovery?

Jernej
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  • Using db_dump -p <wallet file>, do you see anything lines that contain ckey or key? Does the output have HEADER=END near the start of the output and DATA=END at the end? – Ava Chow Jun 13 '19 at 23:28
  • Yes, there are plenty of lines with \0key entries and indeed, both HEADER/DATA entries appear. Also if it helps db_verify says the DB is fine. The wallet was created with a fairly old client (2010?) – Jernej Jun 14 '19 at 06:17

1 Answers1

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It sounds like your wallet.dat file is still intact, but some of the environment data has gotten corrupted (possibly due to moving wallet files).

Try doing

db_load -r lsn wallet.dat

This will reset the LSNs in the wallet.dat file which should cause the errors in the db.log to go away. Once you do that, delete the database/ folder and start Bitcoin Core.

Ava Chow
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  • This seems to make the wallet load just fine, though I wonder if all keys were erased? Is this error msg expected? 22019-06-14T16:40:30Z [default wallet] Keys: 0 plaintext, 0 encrypted, 0 w/ metadata, 0 total. Unknown wallet records: 0 ? – Jernej Jun 14 '19 at 16:41
  • That doesn't sound good. It seems like all of the keys were erased, and that's not supposed to happen. If you do db_dump on the file again, do you see what you saw earlier? Do you still see lines beginning with key? – Ava Chow Jun 14 '19 at 18:43
  • Yes I can still see that. As a matter of fact diff seems to be saying that the two dumps are equivalent. – Jernej Jun 14 '19 at 18:59
  • Don’t use -r lsn you can lose data. – EtherX Dev Feb 21 '22 at 01:42
  • did that, it worked for me, pywallet sees my addresses now and bitcoin core doesn't crash on import (still scanning, though) – Didi Kohen Feb 22 '23 at 14:18
  • where would you input the command db_load -r lsn wallet.dat? I tried doing this in the node window console window and I got Method not found (code -32601) using v26.0.0 – Jon Grah Mar 02 '24 at 13:51
  • trying that command db_load -r lsn wallet.dat using bitcoin-cli.exe and I get an error: error: timeout on transient error: Could not connect to the server 127.0.0.1:8332 (error code 1 - "EOF reached")
    I don't know if my wallet.dat is fully corrupted or just partial. It is just the wallet.dat and I have the encrypted password for the wallet.dat file. I was able to use a java program and decrypt/dump some keys . the db.log file showed similar file unknown has LSN 1/151495, past end of log at 1/28... So I assumed i could just load wallet in and get it to work somehow.     – Jon Grah Mar 02 '24 at 16:02
  • @JonGrah db_load is an external tool, not one of Bitcoin Core's commands. It comes with BDB and you have to use the terminal or command prompt to use it. – Ava Chow Mar 02 '24 at 16:25