Berkeley CSUA MOTD:2001:February:27 Tuesday <Monday>
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2001/2/27 [Uncategorized] UID:20708 Activity:nil
        Stop deleting my troll anotations.
2001/2/27 [Computer/Networking] UID:20709 Activity:high
2/26    router question: sharing static ip address, but pc's in lan have own
        machine names and web servers. how does router know which machine a
        url refers to if the url just has the ip address in it?
        \_ What's running NAT?  Is it a linux/windoze box or one of those
           NAT hubs/switches/routers?
          \_ pc 's and linksys router.
             \_ Is the idea you want your web server accessible from
                outside your LAN?
                \_ yes but there are 2 computers w/ web servers, both need to be
                accessible. The hope is that the router would disintiguish by
                MAC address but the 2 machines would have the same ip.
                \_ Let's say I request the web page
                   <DEAD>www.yermammy.com/foo/bar.html<DEAD>
                   Your browser will put the following in the HTTP request
                   header:
                   Host: <DEAD>www.yermammy.com<DEAD>
                   Now, I'm not sure if linksys routers do this, but the
                   way it would work is that the router would see the
                   packet is going to port 80, look for and interpret
                   the host field, look at a mapping of host field
                   settings to local IP addresses (which presumably you
                   have set), and finally direct the packet to the IP
                   address of the appropriate web server.
                \_ how could the router tell which IP packet is destined for
                   which machine?  Incoming IP packets aren't going to contain
                   MAC addresses.  You'll need to have the web servers use
                   different ports.
                   \_ Yeah, this is the most straightforward way.
                      <DEAD>www.yeremammy.com<DEAD> (port 80)
                      <DEAD>www.yerbrother.com:81<DEAD>
                      and then port forward.
                   \_ unfortunately, the 2 "web servers" are actually DAQ board
                      cards that require an IP addresss but use the same port
                      (no way to change port) even if they have unique IP
                      addresses, the outside would still point to 1 ip
                      address/hostname and same port for both of them.
                      \_ web server 1:  192.168.0.1:80
                         web server 2:  192.168.0.2:80

                         port maps:
;                        router:80 -> 192.168.0.1:80
                         router:81 -> 192.168.0.2:80
                         \_ You've gotta stop posting useful info to the motd.
                            People will come to expect something better than
                            the typical trolling and then what?
2001/2/27 [Reference/Tax] UID:20710 Activity:high
2/26    Is tax software like TurboTax good for people who trade stocks and
        just purchased a home last year carring a mortgage?  I mean is it good
        enough to guide you through all the misc stuff like county tax, escrow,
        point fees, etc. and squeeze in every cent of possible legal deduction
        one can claim?  I'm thinking about whether I should use TurboTax or
        get a tax accountant.  Thanks.
        \_ get a tax accountant, doubt TT is that optimal.  (otherwise, there
           will be no tax accountant)
            \_Falacious argument
           \_ Accountants become more valuable the "weirder" or more complex
              your situation is. This guy's situation sounds fairly normal.
              Then again, he sounds like an idiot, so...
                \_ Therefore, as an idiot, he should get a tax guy to do his
                   taxes.
2001/2/27 [Computer/SW/Compilers] UID:20711 Activity:high
2/26    I assume GDB will allow me to do a trace on any core dump. correct?
        Is there a better way? (pedants:  if so what?)
        \_ I use gdb all the time to analyze core dumps. The problem is
           that gdb gives this facad of a horribly complicated debugger
           which scares people away.  You just need to start off with
           the basics. Compile and link everything with the -g option.
           That's all you need. you can invoke gdb from the shell or emacs
           by calling gdb a.out core (substitute a.out with your program).
           bt is you best friend for finding where a program crashes.
           You're on your own from there. It's sad, I'm not even a
           software engineer and I use debuggers more often than most of
           them do.
                \_ I use Java.  I don't need to debug.  My programs are
                   guaranteed bug-free by Sun.
        \_ i can't think of anything better than what gdb+emacs does.
           what feature do you need? -ali
2001/2/27 [Health] UID:20712 Activity:high
2/26    I've converted my small network (10 workstations) to NIS+.  It's a
        pain in the ass to manage.  Is solstice any good at managing them?
        do I have any other choice?  Thanks.
        \_ DNS
           \_ wtf does DNS have to do with NIS+? Most sites that use NIS+

troll   Stop deleting my troll anotations.
        \_ Use better annotations: t = troll, w = winston, etc
        \_ Use better annotations: h = hamster, w = winston, xxx = rebecca lord
           etc
              use it mainly for things other than host name db.
        \_ LDAP
        \_ hessiod
                \_ ew.
        \_ get a nocmonkey or a labrat
        \_ There is no secure alternative to NIS+, save MAYBE hesiod/moira.
           Come on, it shouldn't be THAT bad to manage. what's giving you
           the headaches?
           \_ what about netinfo?
2001/2/27 [Computer/SW/Languages/C_Cplusplus, Computer/HW/Memory] UID:20713 Activity:high
2/26    Hey folks, I'm looking for something like Purify but cheap.
        What do people do for C programming to guard against memory
        bashing and leaks, other than write their own malloc and
        buy expensive software from Rational?
        \_ wasn't there some kind of program to analyze C code for
           no no's. I think it was called something like lint.
              \_ uh, lint is a syntax checker. it does not figure
                 out if your code has memory leaks.
           \_ memory bashing.  memory leaks.
              \- wasnt there something called electric fence or something
              like that? --psb
                \_ Yes.  -lefence on some Linux systems, or you can go
                   and get the library.  However, efence just puts illegal
                   pages before and after every memory allocation.  This
                   means that if you write outside of the bounds of any
                   allocation, it seg faults immediately there, showing
                   you the memory error immediately if you're using a debugger.
                   This is VERY demanding of memory however, and slow.
                   Memory use will 10x, speed will .04x.  efence is in NO way
                   as good as purify....  --PeterM
2001/2/27 [Computer/Networking] UID:20714 Activity:kinda low
2/26    I want to buy a cable modem instead of renting AtHome's.
        Recommendations?
        \_ It's $5 a month.  You'll never make the money back.  I recommended
           you rent.  They'll change the standard long before you make up the
           lost rent.  And then when you lose net and call them they'll say,
           "Sir, according to our records you're not using an @home rented
            network device.  We suggest you buy a new one or we can rent you
            one for only $5/month plus a $75 install charge."  As a modem
           renter with a broken modem, they send out a truck in a few days
           at no extra cost and refund you the lost net time.
Berkeley CSUA MOTD:2001:February:27 Tuesday <Monday>