Problem with connection database
don_mccall at hp.com
Mon Aug 27 13:10:08 GMT 2001
I haven't had as much time as I would like to look at this, and I'm not as
up on the tdb stuff as I would like,
so I'm posting my initial observations back to the samba-technical list as
well, in hopes these will suggest a course of action to someone more
knowlegable - to me it appears to almost be a race condition of some sort:
All of the bad magic number reports in the log all boil down to the
following magic numbers:
And of course
magic 0x26011999 is reported when a free call is made, because this is the
TDB_MAGIC number, not the TDB_MAGIC_FREE number... what does this mean?
something crapped out before changing the magic number to free_magic, but
somehow put it in the list to be freed???...
The offsets reported all boil down to:
and the offsets where it is reporting bad magic because it's NOT
Ok, we are trying to FREE the above three offsets;
the 1st to got bad magic when the were being tried to
read/write or something as well; maybe comparing what was going on when it
was being freed as opposed to being allocated/read/wrote, and the timing of
that might give us some clues....
We also have a bunch of tdb_oob len xxxxxxx beyond eof at
at the following len/eof's:
1111638598 73732 >>> this is 0x42424246
1111638598 90112 in fact all of the
1111638618 24576 ones in this range look
1111638618 65536 like we just have the initialized
1111638618 73732 memory except for last byte<<<<<<
With all this, it APPEARS that a link in the list is broken, so we are just
following out to 'random' offsets in the tdb file; we are prevented from
making really BAD mistakes by the fact that the TDB_MAGIC for each record is
checked, and processing stops at a bad magic number; but how the link got
corrupted to begin with is still evaiding me...
I haven't been able to pin down the initial corruptor in the logs; we may
have missed this, and are now seeing only the results of a corruption whose
log entry has already wrapped.
Hope this will suggest something to some one more knowlegable on the tdb
than myself. I still have your logs, etc. if someone else on the list
wishes to help out.
From: Claus Svarer [mailto:csvarer at nru.dk]
Sent: Friday, August 24, 2001 5:33
To: MCCALL,DON (HP-USA,ex1)
Subject: Problem with connection database
Our server have now recreated the connection.tdb error again. I have
made a gzipped tar file of all the log and lock files that was at the
server when it chrashed (attached to this mail). I don't know if you can
find out what happens, but as you know the error message is:
fog:/users/csvarer 22 : smbstatus | more
INFO: Debug class all level = 1 (pid 843 from pid 843)
tdb(/usr/local/samba/var/locks/connections.tdb): rec_read bad magic
0x42424242 at offset=5656
If I search int the log file I can find several machines that sees this
problem. At the time where we observed the problem no new machines was
authorizing against the samba server.
More information about the samba-technical