Gentoo Archives: gentoo-user

From: meino.cramer@×××.de
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Re: Need help: Filesystem (ext4) corrupted!
Date: Tue, 03 Sep 2013 15:57:11
Message-Id: 20130903155659.GA3916@solfire
In Reply to: Re: [gentoo-user] Re: Need help: Filesystem (ext4) corrupted! by Francisco Ares
1 Francisco Ares <frares@×××××.com> [13-09-03 17:23]:
2 > 2013/9/3 William Kenworthy <billk@×××××××××.au>
3 >
4 > > On 03/09/13 11:26, meino.cramer@×××.de wrote:
5 > > > William Kenworthy <billk@×××××××××.au> [13-09-03 05:08]:
6 > > >> On 03/09/13 10:45, meino.cramer@×××.de wrote:
7 > > >>> walt <w41ter@×××××.com> [13-09-03 04:15]:
8 > > >>>> On 09/02/2013 09:15 AM, meino.cramer@×××.de wrote:
9 > > >>>>> The rootfs and $HOME of my embedded system is stored
10 > > >>>>> on a 16GB SD-card (about 5GB used, rest free). The FS
11 > > >>>>> is ext4.
12 > > >>>>>
13 > > >>>>> Since the system hangs for unknown reasons several times
14 > > >>>> Does it hang at a predictable point, like during boot, or poweroff?
15 > > >>>>
16 > > >>>> I know almost nothing about SD cards (yet). Do they develop bad
17 > > >>>> blocks like other storage media? I notice fsck.ext4 has a -c flag
18 > > >>>> to check for bad blocks.
19 > > >>>>
20 > > >>> No, it hangs while compiling or while updateing (eix-sync; emerge ...).
21 > > >>>
22 > > >>>
23 > > >>> I did the following now:
24 > > >>> I did a binary image backup with dd of the sdcard.
25 > > >>> I made a backup of the all files from the bad fs with tar.
26 > > >>> I say "YES" to fsck to fix what it found.
27 > > >>> I made another backup of the all files from the bad fs with tar.
28 > > >>> I md5summed both tar archives and found them identical.
29 > > >>>
30 > > >>> Now...is the conclusion correct, that the identical md5sum
31 > > >>> indicate, that the fixed error of the fs only had impact to
32 > > >>> already invalidated data?
33 > > >>> Or whatelse could this indicate?
34 > > >>>
35 > > >>> Best regards,
36 > > >>> mcc
37 > > >>>
38 > > >>> PS: What come mind just in this moment:
39 > > >>> Can I ran fsck on an binary image of the fs which I made with dd
40 > > somehow?
41 > > >>>
42 > > >>>
43 > > >>>
44 > > >>>
45 > > >>>
46 > > >> Have you run out of inodes? - ext 4 has had very mixed success for me on
47 > > >> solid state. Running out of inodes is a real problem for gentoo on
48 > > >> smaller SD cards with standard settings.
49 > > >>
50 > > >> BillK
51 > > >>
52 > > >>
53 > > >>
54 > > > Does this error message from fsck indicate that? I am really bad in
55 > > > guessing what fsck tries to cry at me ... ;)
56 > > >
57 > > >
58 > > >>> solfire:/root>fsck.ext4 -f -p /dev/sdb2
59 > > >>> rootfs: Inodes that were part of a corrupted orphan linked list
60 > > found.
61 > > >>>
62 > > >>> rootfs: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
63 > > >>> (i.e., without -a or -p options)
64 > > >>> [1] 18644 exit 4 fsck.ext4 -f -p /dev/sdb2
65 > > >>>
66 > > >>>
67 > > > Is there any way to correct the settings from the default values to
68 > > > more advances ones, which respect the sdcard size of 16GB *without*
69 > > > blanking it...a "correction on the fly" so to say???
70 > > >
71 > > > And if not: Is there a way to backup the sdcard and playback the files
72 > > > after reformatting it by preserving all three time stamps of the
73 > > > files (atime is deactivated via fstab though) ?
74 > > >
75 > > > Best regards,
76 > > > mcc
77 > > >
78 > > >
79 > > >
80 > > >
81 > > >
82 > > df -i - if you get 100% iUSE or near to it thats your problem ... I have
83 > > seen that error message you give as a result of running out of inodes
84 > > corrupting the FS.
85 > >
86 > > No, your only way out is to copy (I use rync) the files off, recreate
87 > > the fs with max inodes ("man mke2fs") and rsync the files back. Once an
88 > > ext* fs has been created with a certain number of inodes its fixed until
89 > > you re-format.
90 > >
91 > > I get it happening regularly on 4G cards when I forget and just emerge a
92 > > couple of packages without cleaning up in between packages. On 16G
93 > > cards, its compiling something like glibc or gcc that uses huge numbers
94 > > of inodes at times. On a single 32G card I have, the standard settings
95 > > have been fine ... so far :)
96 > >
97 > > Billk
98 > >
99 > >
100 > >
101 > Just my 2 cents: while updating I think it would it be a good practice to
102 > have some sort of external storage (even networked) and do a unionfs with
103 > the working file system. Some folders inside /usr use to keep almost half
104 > (more, sometimes) of all files in my systems (like "/usr/portage" ,
105 > "/usr/src" and "/usr/include" , which are not needed while not under system
106 > maintenance).
107 >
108 > Francisco
109
110 Hi Francisco,
111
112 GOOD point!
113 Only one thing "forbids" this:
114 I often commute between two places. I bought this little embedded
115 computer to do try this or that with it at both places. I have
116 internet access at both places but only at home there is my PC
117 with Gentoo Linux.
118 I dont want to miss Gentoo-hacking ;) at one of the places... :)
119
120 Best regards,
121 mcc