Operational Defect Database

BugZero found this defect 2503 days ago.

MongoDB | 374613

[SERVER-28820] Recovery failed: WT_NOTFOUND: item not found

Last update date:

8/6/2018

Affected products:

MongoDB Server

Affected releases:

3.2.4

Fixed releases:

3.5.9

Description:

Info

My server broke down and all I had is copy of database files in /data/db. No proper mongodump, only files. After restoring my VPS from snapshot, I tried to run mongo, get error (see in attachment) Answering to your question: 1. Which version of MongoDB was the original mongod using? Original was 3.2.4. However, I already updated to 3.4.3 with hope that this will be fixed. 2. What method do you use to create backups? That is the problem, that I didnt have mongodumps. Only *.wt files. 3. Have you ever manipulated (copied or moved) the underlying database files? If so, was the mongod running? No I didnt touch files. After restoring from snapshot, server state was same as before server fault. Please find all screenshots and WiredTiger.wt/ WiredTiger.turtle files. Is it any chance to restore from unclean shutdown only with *.wt files.?

Top User Comments

xgen-internal-githook commented on Tue, 25 Apr 2017 16:02:48 +0000: Author: {u'username': u'sueloverso', u'name': u'sueloverso', u'email': u'sue@mongodb.com'} Message: SERVER-28820 Add a few error path messages in logging. (#3402) Branch: develop https://github.com/wiredtiger/wiredtiger/commit/3f02e205906c487376a04cd936888398913161c4 kasperpro commented on Sat, 22 Apr 2017 09:23:07 +0000: Hello Sue LoVerso, I made steps that you have mentioned. I was able to get mongo running! Regarding journal files, unfortunately I have copy of April 4th backup (the one that I have sent to you was April 7). If it will help to investigate, I can sent to you journal files for April 4th. Anyway, thank you so much! Now I am able to make mongodump and recover my data. sue.loverso commented on Thu, 20 Apr 2017 18:41:57 +0000: Hello kasperpro. There is definitely a problem with the journal files. As my earlier comment implied, they're zeroed out or removed. Please investigate what may have happened there. I was able to get a mongod up and running on your data with the following steps: Move aside the journal directory to journal.old or whatever name you want. Run mongod with --repair --nojournal. Several of the tables need to be repaired. After that completes you should be able to restart mongod with --nojournal to access your data. Once your journal investigation is done, you can restart mongod with the journal for greater durability (and remove the old directory). sue.loverso commented on Thu, 20 Apr 2017 15:24:04 +0000: The good news is that with your tarball, I can reproduce the error and investigate where exactly it is coming from. Thank you for uploading the information. sue.loverso commented on Thu, 20 Apr 2017 14:25:17 +0000: Hello kasperpro, I have downloaded the tarball, you can deactivate the link. I will remove all files when this ticket is complete. Can you tell me about your journal directory? The journal files in the tarball are effectively empty. The first log file contains a few log records that are for system, internal information. All the rest of the log files are zeroed (WiredTiger will create a new log file on each restart attempt). The two error message screen shots show one restart with journal enabled and one without it. Did you switch back and forth with journal on/off? Is there any possibility that the journal directory is on a different file system and that directory could be shared with another mongod process? kasperpro commented on Thu, 20 Apr 2017 05:15:59 +0000: Alexander, please find database files copy. Let me know when I can deactivate link. alexander.gorrod commented on Tue, 18 Apr 2017 19:36:44 +0000: In order to understand better what is happening we would need a tarball of your dbdir, including the journal files. Would you be willing to provide that? If so can you give us some indication about how much data is involved? kasperpro commented on Tue, 18 Apr 2017 03:45:33 +0000: Still getting error, please see in attachment - debug_error1. The only one difference is that now throwing exception in different line: wiredtiger_kv_engine.cpp 26 mark.agarunov commented on Mon, 17 Apr 2017 17:50:32 +0000: Hello kasperpro Thank you for the report. I've attached a repair attempt of the files you've provided. Would you please extract these files and replace them in your $dbpath and let us know if it resolves the issue? Thanks, Mark kasperpro commented on Mon, 17 Apr 2017 13:44:46 +0000: BTW related with ticket SERVER-24435

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