OS : SuSE linux 8.1

Hello,

I've had a power down on a IBM eserver 205 under SuSE linux 8.1.
At boot it begun with fsck /dev/sda5 and stopped rapidly saying
that fsck had to be run manually.
Then a message displaying entering maintenance mode and asking for
root login or CTRL D to reboot.
I logged in and took a look at the mounted devices. None of the hard disks.
I launched fsck /dev/sda5
Then a lot of questions appeared to repair files and inodes.
I answered all by the default answer because I thought the software would take
better decisions than I would. This ended correctly.
I've then rebooted.
The machine is operational BUT a part of /usr/bin seem to have disapeard.
That's to say that some commands are no more recognized.
I've some important bash scripts to run and for cut/lessopen and other
commands at execution the error message is unknow command. And that's right
these binaries are not present in /usr/bin (where they are usually located).

Here my questions
1) what is this maintenance mode
2) how can I reconstruct /usr/bin
3) is there an option or an utility to repair a linux system

I'm looking for a quick answer because the problem happened on a customer's
production machine.
Thanks for any help or hints
Nadine

what was the filesystem ?
some filesystems are better than others at resisting damage from power cuts.
maybe in the future consiter using reiserfs or XFS or JFS.

im not sure if there are utilities to resue the partiton, that all depends on what filesystem you are using.

i would recomend restoring the partiton from a recent backup (you DO backup right ?)