TDB corruption on sam.ldb tdb files

Andrew Walters aw-sambalists at
Fri Sep 21 16:49:44 MDT 2012

Thanks to Andrew Bartlett and Ricky Nance for your replies.

Because I'm responding to both of you about similar stuff that you both suggested, I'll omit quotes to keep it brief.

For reference to anyone coming across this later, the messages I'm replying to are these two:

I've been slow getting back to this as Saturdays (NZ time) are my best maintenance window time, given the school can still operate off the bad ldb.

It's a single domain controller envirionemt - no replication.

tdbbackup works on sam.ldb and sam.ldb.d/* EXCEPT sam.ldb.d/DC=AD,DC=(domain name), where it fails with:

tdb_rec_read bad magic 0x6863733d at offset=1773572
failed to copy DC=AD,DC=SMS,DC=SCHOOL,DC=NZ.ldb

... which are the same magic and offset values given when samba-tool dbcheck --reindex and ldbedit can't remove the index.

In the meantime, since it's most likely your Friday evening as I type this, and since I can still browse the directory, and application of GPOs, user accounts, group memberships, and therefore permissions all still work, I might try my luck setting up a VM with another copy of samba4, and try to alternately replicate and vampire the domain over to there to see what comes out the other end.


Andrew Walters

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