--- Paul Taylor
HI all:
How many people on the list have had a Linux server hacked to the point that it needs to be reinstalled?
Do you mean this from the point of the computer being compromised maliciously, or via your own tinkering? If the former, then never. If that latter, then only once. Actually, people that say: "Oh, I had to reinstall Linux today, since XYZ didn't work" tend to do so because they're operating under the assumption that Linux acts like MS-Windows in that "a reinstall cures all". Not so. One of the challenges I often set people, is to _fix_ their Linux box without reinstalling. It's a really good learning-curve, and through doing it, it's surprising at just how much one can learn. Of course, I realise that it isn't always that straight forward -- especially where the machine in question is in a critical environent. But consider for a moment why you would need to reinstall. If your machine is "broken" it could be for any number of reasons. These might include: * A specific application fails to run anymore. * The init sequence fails. * Some applications randonly start to crash * The kernel panics. In all of those cases, it is trivial to attempt to ascertain why. If the first point, for instance were a daemon -- that is, a "service" program then: /etc/init.d/foo start will often tell you if it was successful or not. If it isn't then most daemons log to /var/log/<application>/<filename>. Tailing that file, might prove useful. The classic example here, is squid. I have had squid fail on few times. But nothing was being written to the logfiles. It transpired /var was full, so no logfiles could be written to. The caveat here is to always check the output from "df -h". Hardware failures though, tend to present themselves in many different ways -- but the precursor is usually where multiple applications that used to work, start to itermittently crash with SIGSERV or SIGABRT, or SEGFAULT. -- Thomas Adam ___________________________________________________________ Yahoo! Messenger - NEW crystal clear PC to PC calling worldwide with voicemail http://uk.messenger.yahoo.com