If you happen to need to check your linux filesystem, which is mounted read-write, and for some reason you do not want to reboot, then the simple sequence of commands listed below should help you. Note, that the commands provided put you into single-user mode, which kills web-server and mysql daemon.

So, running e2fsck on a live (mounted) filesystem isn’t recommended – and f2sck asks if you really want to check the rw-mounted FS (be sure to answer ‘n’o). If the FS you want to check is root (/), you cannot also re-mount it read-only – unless first you go to single-user mode:

init 1

Now you can re-mount your FS read-only:

mount -o ro,remount /dev/cobd0

(/dev/cobd0 is my device, replace it for your device when repeating step-by-step).
Filesystem is now read-only, and it’s safe to run e2fsck:

e2fsck -D -C 0 -f -t -v /dev/cobd0

e2fsck options are optional:
-D: optimize directory structure
-C 0: show progress
-f: force check (use if you get “volume is clean” with no check)
-t: e2fsck timing statistics
-v: verbose mode

Finally, return to your previous user mode:

init 3

I enjoyed this article, while trying to make the R environment on Windows process some 16 microarrays, using some memory-intensive algorithm… Well, after several hours of processing and gradually increasing the memory use, R script failed with memory-allocation error.

It’s interesting, but running the same script in Topologilinux, launched from within Windows, did the trick. Though being a simulated environment, it was slower, and page-swapping was really heavy with only 0.5GB memory.

Topologilinux ‘BSOD at launch’ problem solution is at the end of this post.

Topologilinux is a special linux flavour, which is especially fit for the newcomers to the *nix world. The motto of Topologilunux is ‘Running Linux inside Windows’ – and that is what it does. Even more – you can run it inside windows, or you can boot into it and work Linux-only – in both cases the system is the same.
Personally, I consider this kind of setup extremely useful for users who are strongly used to working in Windows (or just stuck with windows for too long), but at the same time are inclined to script a bit (be it bash, Perl, PHP or Python), to run server applications, write cross-platform programs, to test something or just play with software. With Topologilunux, it’s perfectly fine to work in DreamWeaver on your windows machine, and launch Topologilinux with apache+php+mysql to serve as a testing server – on that same machine. You can easily replicate the needed server config, and play with it the way you wouldn’t if that was the production server.
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