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
        >=ïïïïïï2[jïbïïnwïïïïïïïï in md5sums 
for irssi-scripts: ïïïïgV{Úï
                                 
ïNïïïLïïïMg{ïïïï.ïïïïï`ïïïïÓLïïïj$ïkC1'ï
 ïïSï ïïïÝïï
        debsums: invalid line (2) in md5sums for irssi-scripts: 
ïïïïgïDPHïï     ìïïï}ï]gïïïïïNïciï5ïh
        
ïwïW{SZïïqïïF_ïsRï[ïïïieïA|ïïSvïï@ï@ïï;ï5ï'#cïï$ïïl%ïïïï
 ïïTïïï$ï!dïBïy
        debsums: invalid line (3) in md5sums for irssi-scripts: 
ïïïïï-ÄEïïyqï/7Ä>ïïïïïïïÐïïïïïïVuïïïïV
        ï+ÉAïfïï:%Oïï_lïïï}ïïïïïï}ï 
ïï1ïïïÈÏïï=?ïï&ïïïïïïïïFïïïmTïtrZï
        
ïïï1ïïïenO%.ïYNïï=ïkïï@ïïïï\{8Éwïxïïïïzïï-P!gïjïïïïQV9uïïïïïï)ïmïïï5ïlï8l
 ïRk5ï;MïïïRïïï
                                                                                
                ïfxïïO
        
gÑïï;ïïïïÙïHYfrcïï9ïïïïïuïqïïïOxß`ïïïï~_ïÆ2"J;ïQ$vl?ï{ï=Vïïïïïï
 ï[ïï\ïdïïnï!ïUHïïYïDïïj2Iïïï*ï
        
[ïcïïGïïïïïïï[ïïh*ïïïïïïïïï2Aïïm&ïïïïïïïïïïÞGÐï;Rï0ïïÌïïï
        ...
        
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-KÃnig

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