FIRST OF ALL: Before making ANY changes to system files, create backup copies of it's original representation. This simple procedure helps you to save you time and money, believe me. If you read this and does not backup your files, try to ask somebody on this site to send you necessary files in untouchable state.
NOTICE: I like graphical interface, but years of working as system administrator makes habit to work in console all the time. So all steps will be described in console. If you be an expert in linux, you probably understand all steps without any problems. And as expert you can avoid of using very comfortable manager like Midnight Commander. It's your choice. I described steps in manner for most non expert users, in most simplest manner, as I think.
If you have any comments or additions, post them nearby.
And sorry for my bad english, if it does, I am just learning :)
DISCLAIMER: If you break your book totally following this steps, I take no blame. I just described, how I restored my book and if this not work for you, it's not my fault. Do it on your own risk!
Even if your system don't booting after this steps, you can try this Rescue Procedure.
Ok, here it is, a simple situation, anybody can go in.
You working in ssh console of a book, trying to configure some applications, making changes to critical system files. When done, you making book to reboot and… nothing happens! Blue flash light does not came up, book does not boot anymore. First guess: "I make some wrong changes…"
If you get in situation like this and want to save system, just roll back to older files. How? Read further.
Instruction is valid for both single and double disks book edition. If need some advanced explanations, it described in addition.
Remove drive(s) from book container. How to do it, read here
Remove the HDD from MyBook World Edition (PDF Link)
For this step you will need USB stick or empty CD disk.
Follow this link and make your own Slax Live CD distributive. How to make it, described foregoing link.
Connect drive(s) to computer. If you had two drives edition, connect both drives. Then load slax from USB stick or CD drive.
When slax finished loading (by default it's loading in KDE), open terminal window from bottom panel of KDE (icon with black square).
Type in console:
and press enter. It opens Midnight Commander (if you ever worked in Norton Commander, it's appearance looks similar. If you don't, take some time, to meet with it closely, it's help you in the future, trust me! :)).
Move to /mnt.
You will see mounted disks and raid arrays. If you connected two drives from second edition book, you will see md1, md3 and md4 directories or something like that. It's your raid arrays of book, like they was mounted on working book's system. Single book drive may appears like sda1, sda3 and sda4.
Directory md1 (sda1) is your root directory of a book. md3 (sda3) directory contian book's /var directory. And the last md4 (sda4) directory contain your /shares/internal book's directory or in other words, it contain your shared PUBLIC catalogue.
On this step you can backup you files stored in PUBLIC directory.
If you DON'T SEE this directories or this directories are empty, probably your disk's partitions has errors. If that so, proceed to step 7. If directories and it's content are visible and okey, proceed to step 6.
Unmount book's partitions. If you connected two drives, type in console:
If you had single drive, type in console:
After unmount procedure complete, move to /mnt and check all directories you just unmounted. All of them must be empty. If they are not, close all working programs, close console you working in and return to step 4.
Only after make shure, that this step is totally completed, proceed to the next step. Otherwise, you may completely break you system and the only way to back your book will be this Rescue Procedure.
WARNING: If proceeding this step just after typed command and pressed enter button you will see message informs you, that partition is mounted and asking you to confirm system check, press N button and back to the 6 step.
First of all, you must check your book's filesystems for errors. To do that, type in console:
For single drive it may looks like:
Every time program will find an error in your book's filesystem, it will ask you to correct them. Type Y button on your keyboard to confirm action.
Now proceed to roll-back procedure. It's simple. Just rewrite modified files with their backup copies to be shure, that system can boot up again.
Of course, you may say: "Why roll-back? I can just undo changes I made or make right ones". It's your desicion. But this instruction described, how to make system bootable again and, as I think, the only right way to do it, it's roll back to working files! After successfull boot up procedure you can go in ssh and make any other changes as you like.
Now after you roll back modified files you may turn off your computer. To do that, press little gear with K letter in bottom panel of KDE (most left button) and choose Turn off in appeared menu. Then press Turn off button on next window.
10 STEP (FINAL)
After your computer is off, disconnect drive(s) from computer's leads and assembly your book. Then connect power supply to it and press power button.
Be happy as looking how your book booting again!