zlacker

A long time ago, as a novice sysadmin, I spent some unhappy time fixing a broken Solaris server. The problem was fsck was in /usr/sbin, /usr was a mount point on an external drive array that got its power yanked. Challenge: to boot you need to mount /usr, but first you have to fsck it using the binary in /usr/sbin ...

After that I would make sure to have some working (static) binaries for rescue on every *nix system, tar at least, and on Solaris an extra /usr/sbin/fsck under the /usr mount point). You can fix a lot of things with tar, sed and netcat.

>>mrspur+(OP)
These days a static-linked copy of busybox on the root partition is usually enough; assuming you have the space for that. A 'full' initramfs can also help in case you need to bring over a USB drive of tools from another system or have changed hardware.