Berkeley CSUA MOTD:1998:November:25 Wednesday <Tuesday, Thursday>
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1998/11/25 [Computer/SW/OS/Linux] UID:15021 Activity:very high
11/24   Linux question:
                One of our linux servers at work allows anyone to type "su" to
                become root.  Someone did this and changed the root password
                from it's default state of not having a password to having
                a password.  To make a long story short, someone else was
                still logged in as root and erased the entry in the
                /etc/shadow file, so we no longer have the problem.  However,
                how do you determine which user/IP address the change
                originated from?  Keep in mind that the time stamp was changed
                once we fixed the /etc/shadow file, so we can't use the
                original time stamp to help track anyone down.
                \_ I don't suppose you have a sulog, or even /var/log/messages
                  syslog messages reporting successes/failures of su commands?
                \_ of course a good hacker who knows what they're doing will
                   have erased all trace of themselves, and installed
                   something fun like the RootKit, assuring future backdoor
                   access to them and their buddies.
                        \_ you don't need to be a particularly good hacker
                           to break into a linux machine with a blank root
                           password.  Christ, set a password and get on
                           with your life.  -tom
                \_ No root password?  You are fucking stupid and deserve
                   what you get.  SET A FUCKING PASSWORD!  Use sudo if you
                   must.  You're running your unix box like a win95 machine.
                   Even if you do find logs, you can't believe what they say.
                   A malicious person wouldn't have erased all traces but
                   changed the logs to point to _someone else_.  Go hire a
                   real SA and stop letting engineers play root.  It isn't
                   a game.
                \_ Well, thank you for missing the point and responding with
                all the lunacy of a religious zealot.  For god's sake, we're
                behind a firewall, and even if we had a root password, it
                would be told to most everyone anyway.  The linux box is used
                as a test server.  It's ok that it's running "like a win95
                   \_ Something you failed to mention.
                machine".  And it wasn't a goddamn hacker, ok?  What kind of
                                \_ No one said it was.  They said you're
                                   stupid.
                idiot would hack his way behind the firewall, figure out
                        \_ A malicious employee who already works on that
                           side of the firewall.
                someones' login/password, go to superuser, hack at the system,
                cover his tracks, and then change the root password so we
                would become immediately suspicious?
                THINK, IDIOTS, THINK!  The simple, original question, was:
                Can you tell who logged in, then typed su, and then ran
                passwd.  var/log/messages says root did it, and gives a number
                that I'm guessing is the PID.  Can you then tie the PID to
                a user or IP?  Thank you and I apologize for being cranky,
                but it is COMPLETELY unproductive to yell about passwords,
                etc, it doesn't answer the question.  Would you respond to
                "if johnny has $150, and wants to buy a $200 raiders jacket,
                does he have enough money?" with "THE RAIDERS SUCK! JOHNNY'S
                A LOSER!  ARGGGH!"  no, you wouldn't.  Good lord, this is basic
                life skills 101 people.  Oh, also, there's no "sulog". Thanks.
1998/11/25 [Uncategorized] UID:15022 Activity:nil 75%like:15023
11/23   Thanksgiving, so lonely... must download alt.binaries.pictures.oriental
        \_ shut up aaron!
1998/11/25-26 [Uncategorized] UID:15023 Activity:nil 75%like:15022
11/23   Thanksgiving, so lonely... must download alt.binaries.pictures.monica
        \_ shut up aaron!
           ^aaron^cmlee
1998/11/25-29 [Uncategorized] UID:15024 Activity:nil
11/25   A while ago Corel released WP for linux.  Does anyone know where I
        could get screenshots of the thing running?
        \_ http://linux.corel.com
1998/11/25-26 [Uncategorized] UID:15025 Activity:nil
11/24   Anyone have a sample LaTex document I can use to write a thesis-like
        paper?
1998/11/25-26 [Uncategorized] UID:15026 Activity:nil
11/24   http://aries.www.media.mit.edu/people/aries/dutch.mov
1998/11/25-12/1 [Academia/Berkeley/CSUA, Computer/Theory] UID:15027 Activity:nil 62%like:15048
11/25   CSUA ALUMNI! Come to the CSUA General Meeting on December 2!
        There will be a general reunion, and foodP and drinkP afterward.
        Come to where the elite meet for NP-complete!
        \_ someone should keep extra good minutes for those of us alumni
           living too far away to attend - seidl
1998/11/25-29 [Computer/HW/Drives] UID:15028 Activity:nil
11/25   Whoo hoo! Dragon's Lair out on DVD. The ultimate in mindless fun.
        \_ do you mean "DVD for computer", or is there somehow a way
           to play it on a "regular" DVD player?
        \_ there's two versions, one for dvd players and one for dvd-rom
           for computers. they're essentially the same, with the former
           using your remote's joystick and select buttons for gameplay.
           (btw, some dvd movies include simple games as extras)
1998/11/25-29 [Computer/Networking] UID:15029 Activity:low
11/25   Anyone ever taken a look at the following?
        http://www.adaptec.com/products/solutions/satellite.html
        Anybody here use it?  I'm looking at it as a possible way out of my
        medieval net swamp...  -John
        \_ GW = satellite for Internet use requires a phone line modem which
           sends requests to the ISP, which relays that to the satellite,
           which sends you the right info - nasty latency.  Seems like cable
           modems are most ppls sol'ns, with DSL for the $-laden. -jctwu
                \_ not in Switzerland.
                   \_ Specifically, our cable modem setup here is pretty bad,
                      since (a) our physical net is overloaded, and (b) they
                      are doing dynamic NAT instead of giving everyone their
                      own IP, so no netrek.  Thought that the adaptec card
                      hooked directly to a satellite tv-type dish by coax
                      cable.  Point the dish at the satellite and you're
                      on.  But then I don't know whether those things can even
                      transmit that far.  I don't think I have to go through
                      a provider, since that would defeat the whole point
                      of having a satellite network card... -John
           \_ DSL only for the cable-modem impaired. SJMercury had an article
              about a massive cable-modem rollout soon in the South Bay. The
              final sentence of the article: "This covers all areas of the
              SouthBay except San Jose." FUCK!
                \_ it'll collapse when they try to put that many people
                   on it.  They're selling bandwidth at a loss.  -tom
        \_ There is a DirecTV satellite over Europe. Maybe other supported
        ones too. I'll check. Your latency might be too bad for netrek, but
        bandwith for your porn downloads will be good. There is a
        right way to provide cable modem service and there is a wrong way.
        The way Austrian PTT does it for example is wrong. You sit on a
        shared Ether with the whole city, so it is much much slower than it
        could've been. I expect Swiss PTT to be similarly lame. -muchandr
        \_ That about covers it.  The thing that sounds cool about the
           satellite card is the high bandwidth, although you're probably
           right about the latency.  -John
           \_ out-and-back to geosynchronous satellites is over 500ms
1998/11/25-29 [Finance/Banking] UID:15030 Activity:low
11/25   Does anyone know of a credit union/bank that will loan to students
        on a relatively low interest rate? perhaps $2000/1yr?
        Thanks ...
        |_ You could see about a standard student loan, I think they have
           nice rates and interest deferred until you graduate etc.
                \_If you can get yourself a perkins loan, the deferred
                  interest is 5%, as opposed to the adj rate of direct
                  loans which are 7+%.
                \_ Get a credit card with a low introductory rate, and ask
                   for convenience checks.
                \_ Some convenience checks charge 2-3%...read the fine
                   print.
                        \_ Actually, I got a Southwest VISA card with a
                           low introductory rate, and they haven't charged
                           me for using their convenience checks. But yes,
                           do read the fine print.
                          \_ but they do charge the normal cash advance
                             interest, which is typicall 14-19%/yr
1998/11/25-27 [Computer/SW/OS/FreeBSD] UID:15031 Activity:very high
11/25   I'm setting up some cheap PC boxes (PII's and K6-2's) to do some
        number crunching for my PhD project. Since my calculations are just
        pure number crunching and no graphics, I'm trying to decide which
        OS to use. I can't afford (nor do I want) WinNT. Linux? FreeBSD?
        OpenBSD? Others? -- spegg
        \_ What's wrong with using an abacus?
           \_ Abucus? Those things can't do Jack.  Use a slide rule.
        \_ Better yet is if you have a multiproc system which Linux has
           supported for a while and which FreeBSD 3.0 (which just recently
           came out officially) now supports.  Aside from that I've heard
           very few complaints about either OSs.  You'll find more Linux
           binaries around but since you're probably writing your own
           programs that doesn't really matter.  FreeBSD is a bit slimmer
           than Linux (~1MB statically compiled kernel vs ~4MB statically
           linked + any extra dynamically loaded modules).

           \_ you know, I wonder what accounts for this huge size difference.
           \_ get real. Solaris x86 is best for multi-cpu usage.
              \_ oh yeah, i forgot.  but when it comes to single processor
                 performance, i don't think running any one of those OSs
                 will give you a huge performance increase.  They all
                 pretty much execute x86 ELF binaries which are optimized
                 in the same way.  The only difference you might see is
                 how well each OS handles dynamic object files and how well
                 it manages memory for calculations that require a ton of mem.
                 \_ In which case, if you're dealing with virtual memory
                    that far exceeds physical memory, I hear solaris is also
                    the winner.
                        \_ if you'r edealing with virtual memory which
                           far exceeds physical memory, you've already lost.
                           \_ not really.  It happens all the time and is
                              possible because of spatial/temporal locality.
                              Say you're running Gimp with 4 5MB tiff files
                              open a the same time on a 16MB PC.  Chances
                              are the you're not going to be dealing with
           than if there's a real OS running.  You can still tell the
           compiler to generate 32-bit or Pentium instructions.  -- yuen
                              all 20MB at the same time even though they
                              are all open. Hence +20MB virtual vs 16MB
                              physical.
                                \_ First of all, the guy is talking about
                                   number crunching, not image processing.
                                   It is likely that he's going to be
                                   addressing all of the memory he's
                                   crunching with.  And second, no one said
                                   it was impossible--it just is painfully
                                   slow.  disk is like 6 orders of magnitude
                                   slower than RAM.
                                   \_ uhh. "number crunching" applications
                                      usually exhibit greater locality
                                      than almost any other app, if
                                      optimized properly. -nick
                                        \_ which will help not at all if
                                           it's using more than physical RAM.
                                           \_ What part of "locality" don't
                                              you understand, twink?  Nick knows
                                              what he's talking about.
                    \_ Wow, someone actually used the term virtual memory
                       properly.
        \_ Since you're doing number crunching, you'll probably be best off
           with Intel.  I encourage you to benchmark a K6-2, but P-II's are
           superior in FP ability, though perhaps not most cost-effective.
           Your next big worry is the compiler to
           use.  I guess you don't want to pay for one?  Then you're stuck
           with either gcc/g77/g++ (either the GNU flavor or the egcs flavor:
           egcs is likely to be faster).  gcc/egcs can be faster or slower
           depending on how it is compiled!  You may want to spend a day or
           so making sure you have a good compiler + flags.  The OS to use is
           your SMALLEST worry if you're doing number crunching, no graphics.
           Linux/FreeBSD/OpenBSD all use gcc/egcs anyway.  I personally
           use Linux, it works fine for crunching.  I've nothing bad to say
           about FreeBSD either:  both should install easily and be easy
           to manage.  RedHat Linux is particularly easy to install.  --PeterM
        \_ By the way, Scott, your .forwarding address doesn't work.  --PeterM
           \_ just out of curiosity, are you by any chance the same Peter M
              that appears on the gimp splash screen?
              \_  No, that's Peter Mattis.  My login is peterm.  --PeterM
        \_ Actually, since you're just doing number crunching and nothing
           else, DOS may be the best "OS" to use if you're stuck with a single
           processor PC.  Sure it's the lamest OS ever (if you can even
           call it one), but then you'll have the most CPU cycles available
           than if there's a real OS running.  Plus I think (not sure)
           running in real mode is faster than running in virtual mode.
           You can still tell the compiler to generate 32-bit or Pentium
           instructions.  -- yuen
           \_ *I* would certainly not want to have to move from machine to
              machine to manage jobs!  An ethernet card is MUCH cheaper than
              a monitor for a compute-farm, and DOS has nil networking
              capability.  Linux/FreeBSD are worth it for convenience.
              Second, "real" OS's really incur very little overhead, and you
              can even reduce it to a very small amount by increasing the
              time slice each process gets.  SMP machines are a good
              suggestion though:  they're very space/cost effective, and
              linux, at least, does a good job in SMP mode keeping the
              CPU's busy when you run long-running compute intensive jobs.
              Just be sure not to run more jobs than you have CPUs. --PeterM
           \_ If you have other programs running on your system that are
              idle almost no time will be deticated to those processes.
              I'm running httpd on my computer but it takes up about 0%
              of my processor resources so idle processes shouldn't matter.
              Pentium optimized instructions may even be faster because
              they pipeline better and the memory management on unix beats
              the hell out of dos so if you're doing space inefficient
              computations dos will stink.
              \_ even if they wind up doing nothing, you're still wasting
                 cycles  with the kernels occasional interrupts to check its
                 scheduler and find that it has nothing else to do.
                 \_ Yeah, use QNx or ixWorks or code raw assembly
1998/11/25-26 [Politics/Domestic/President/Clinton, Politics/Domestic/President/Bush] UID:15032 Activity:very high
11/25   http://www.drudgereport.com/matt.htm for the most recent info on
        why Clinton should be impeached and shot.
        \_ yeah whatever. i think you should be impeached and shot.
           \_ What do you mean "yeah, whatever"?  If the current
           administration has jeopardized the national security of this
           country, then it should be removed.
           \_ politicians selling out the country's interets  because some
              big contributor asked them to?  Wow, now there's news.  What
              political utopia have you been living in?
                \_jeopardized national security!??? Youre stupid.
           \_ getting a blowjob is close to national security breach?
              \_ I hear the Iraq situation is cumming to a head...
                 \_ but Im sure we'll "pull out" before anything irreversible
                    happens
        \_ What an amazing, realiable source of information.
2024/12/23 [General] UID:1000 Activity:popular
12/23   
Berkeley CSUA MOTD:1998:November:25 Wednesday <Tuesday, Thursday>