Problems with XFS in a power failure

[Uwe Kleine-König <ukleinek@xxxxxxxxxxxxxxxxxxxxxxxxxx>]

Hello,

my machine suffered a power failure while doing a apt-get upgrade.

This damaged several files.  E.g.

        root@cepheus:~# xxd /var/lib/dpkg/info/myspell-en-us.postrm
        0000000: 0000 0000 0000 0000 0000 0000 0000 0000  ................
        0000010: 0000 0000 0000 0000 0000 0000 0000 0000  ................
        0000020: 0000 0000 0000 0000 0000 0000 0000 0000  ................
        0000030: 0000 0000 0000 0000 0000 0000 0000 0000  ................
        0000040: 0000 0000 0000 0000 0000 0000 0000       ..............

while the repaired file has a size of 78 (= 0x4e) bytes.  Some other files got
broken with random data.  I checked with debsums -c and it reported:

        root@cepheus:~# debsums -c
        >=������2[j�b��nw�������� in md5sums for irssi-scripts: ����gV{ڛ�
                                 �N���L���Mg{����.�����`����ӈL���j$�kC1'� ��S� 
���ݏ��
        debsums: invalid line (2) in md5sums for irssi-scripts: ����g�DPH��     
숐���}�]g�����N�ci�5�h
        �w�W{SZ��q��F_�sR�[���ie�A|��Sv��@�@��;�5�'#c��$��l%���� ��T���$�!d�B�y
        debsums: invalid line (3) in md5sums for irssi-scripts: 
�����-ċE��yq�/7đ>�������Ў������Vu����V
        �+ɋA�f��:%O��_l���}������}� ��1���ȴϘ��=?��&��������F���mT�trZ�
        
���1���enO%.�YN��=�k��@����\{8ɔw�x����z��-P!g�j����QV9u������)�m���5�l�8l 
�Rk5�;M���R���
                                                                                
                �fx��O
        gѝ��;����٠�HYfrc��9�����u�q���Ox߀`����~_�ƃ2"J;�Q$vl?�{�=V������ 
�[��\�d��n�!�UH��Y�D��j2I���*�
        [�c��G�������[��h*���������2A��m&����������ޥGЉ�;R�0��̦���
        ...
        
I don't know exactly, but I think the damaged file here was
/var/lib/dpkg/info/irssi.md5sums and debsums repaired it!?

In theory this should not happen with a journaled fs, does it?

This is a 2.6.19.3 kernel, unfortunately tainted by madwifi.
There was nothing logged in dmesg and/or syslog.

        root@cepheus:~# xfs_info /var
        meta-data=/dev/hda9              isize=256    agcount=8, agsize=91619 
blks
                 =                       sectsz=512   attr=0
        data     =                       bsize=4096   blocks=732952, imaxpct=25
                 =                       sunit=0      swidth=0 blks, unwritten=1
        naming   =version 2              bsize=4096  
        log      =internal               bsize=4096   blocks=2560, version=1
                 =                       sectsz=512   sunit=0 blks
        realtime =none                   extsz=65536  blocks=0, rtextents=0

I have to shutdown that machine because of a power cut by my supplier, but
probably I will use a boot cd to bring it up again ...

Best regards
Uwe

-- 
Uwe Kleine-König

http://www.google.com/search?q=1+degree+celsius+in+kelvin