HOWTO: force filesystem check on reboot in a Linux system

Usually, only a superficial file system check is performed automatically on boot up, and it's sufficient; but sometimes it could be handy to force a full file system check (i. e., to run the Linux fsck utility) to ensure the FS is really OK.

1. Classic init (SysVinit): just reboot the system with a special option:

   # shutdown -rF now

2. systemd init: much more interesting: at the boot time, you need to append a special kernel command line parameter (e. g., you can specify it at the GRUB command line):

   linux /boot/vmlinuz root=UUID=... ro fsck.mode=force

P. S. It should then check all the filesystems enabled for checking in /etc/fstab.

References:

1. man shutdown
2. man systemd-fsck
3. man fstab
4. man fsck

Nonsensical minor long-running bug in Ubuntu

The file containing a default Ubuntu wallpaper is still named 'warty-final-ubuntu.png' (in honor of the first Ubuntu release, 4.10 "Warty Warthog"), but this PNG image actually became a JPEG one sometime in 2008!
The following "bug" still affects the "ubuntu-wallpapers" package versions found in the current Ubuntu stable (13.10 "Saucy Salamander") and development release (14.04 LTS "Trusty Tahr") repositories:
https://bugs.launchpad.net/bugs/296538
Nobody cares. Enjoy! :)

TestDisk & PhotoRec: nice tools to recover lost partitions & files

TestDisk + PhotoRec is a nice toolset to recover lost disk partitions (or at least rescue some files from corrupted filesystems) in case of storage media failures, re-partitioning errors etc.
Works for disk images too.
More to say, it's a free & open source (GPL v2+) cross-platform (Linux, *BSD, Apple Mac OS X, Oracle / Sun Solaris, MS-DOS, MS Windows) software.

Presently, in Debian-based Linux distros, TestDisk & PhotoRec have been packaged into a single testdisk package, so you can install both tools at once:

# apt-get install testdisk

FTP search engines: quick list

Usually, the conventional WWW (World Wide Web) search engines can do the Internet search job well, but sometimes (e. g., if you are looking for some particular file name) FTP search, cataloging & indexing engines can be of great help.
Here is a quick list of such sites.

• Мамонт (in Russian) / Mamont FTP Search Engine (in English)
[BTW, "мамонт" means "mammoth" in Russian]
• Gegereka - Internet file search
• Proisk (in Russian & English)
• FileSearch.ru (in Russian) / FileSearching.com (in English)
• NAPALM FTP Indexer
• FileWatcher File Search
• FreewareWeb - FTP Search
• Oth Net Search
• Krasfs (in Russian)
• MetaBot.ru (in Russian)
• ...

Free & open source data encryption software: quick list

Here is a quick list of free & open source on-the-fly filesystem (FS) encryption software.

• Entire disk / volume / partition encryption & "virtual disk" (container file)-based software:
  • LUKS / dm-crypt [Linux (FS driver is implemented at kernel level); encrypted volumes are supported by FreeOTFE in MS Windows];
  • FreeOTFE [MS Windows];
  • DiskCryptor [MS Windows];
  • TrueCrypt [MS Windows, Mac OS X, Linux] (discontinued in 2014-05).
• File-level encryption tools:
  
  • eCryptfs [Linux (FS driver is implemented at kernel level)];
  • EncFS [Linux (FUSE-based FS); experimental MS Windows port exists: encfs4win];
  • antigift (a ccrypt wrapper) [Linux, FreeBSD, Mac OS X, MS Windows].

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Last updated: 2014-06-19