Berkeley CSUA MOTD:Entry 45642
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2025/05/24 [General] UID:1000 Activity:popular
5/24    

2007/2/2-3 [Computer/Networking, Computer/SW/Unix] UID:45642 Activity:very high
2/2     So is there some serious problem with gigabit? I keep seeing problems
        with gigabit devices in 10/100 networks, or vice versa.
        \_ do you think gigabit is some exotic, bleeding edge technology
           just a few people are using?
           \_ All I know is that when I use it in mixed networks, I keep
              running into problems.
              running into problems. -op
              \- there are some cases where you can get unepxected
                 measurements like a 10mbit thru path that might be
                 "faster" than a 10mbit-100-10 path for reasons i wont
                 go into, but if you are getting dramatic failures or
                 really bad performance, it's probably pilot error or
                 something out of control somewhere.
                 \_ "pilot" error?  What, you mean I made a mistake when
                    plugging the wires into the switches? -op
                    \_ you know there is a lot to configuring switches and
                       routers. duplex negotiation, potentially how mcast
                       signaling is handled etc. a colleague of mine found
                       a piece of networking gear flattended because of a
                       but in IGRP handling. from the nature of your
                       description of the problem ["is there a *problem*
                       with gigabit" without mention is the problem,
                       with thruput, latency, packet loss, ethernet frame
                       errors, high cpu load] it seems unlikely anybody
                       will be able to talk you thru it. your brain has been
                       probabilistically estimated as: small.
                       \_ I've tried two different switches on my home network
                          which was working great with 10/100 devices
                          (including my router).  I added a gigibit device
                          which failed to simply plug in to my 10/100 router
                          and work.  It worked if I plugged it into a
                          10/100/1000 switch, but the throughput crashed.
                          Everything is set to autonegotiate.  I've tried this
                          with two different switches.
                          Then one of my coworkers got back from a customer
                          site where the networking wasn't working--using a
                          10/100 card instead of a 10/100/1000 card solved the
                          problem. -op
                          \_ i use gb networking "everyday" for at least
                             3-4 years. i have some number of problems now
                             and then but the technology obviously is
                             solid ... which is not to say there might not
                             be some porrly designed equipment in the
                             space, or some particular pieces might be
                             lemons. we're doing more 10gig work now ...
                             this is actually kinda interesting. this may
                             be the first time in a while when the typical
                             fast computer cannot saturate the link [obviously
                             hw traffic generators and special hackery can].
                             note: i dont know anything about 'home quality'
                             gb networking equipment.
        \_ I have never seen any problems. I think it is you.
           \_ Oh sure, I'm the only guy with a netgear gs105 switch and two
              different gigabit cards. -op
        \_ It may be that the cables you're using aren't up to snuff.  See
           if netstat shows a lot of packet errors.
           \_ If so, why do the exact same cables work great when they're
              transferring only gigabit traffic? -op
              \_ if you want any more help you need to systematically
                 describe the symptoms and the specifics of your set up.
                 you can leave out the details and just say "i'm having
                 problems". come on, dont be a moron.
              \_ you realize negotiating duplex setting and link speed
                 are two different things, right? if you want any more
                 help you need to systematically descibe the symptoms and
                 the specifics of your set up. you can leave out the details
                 and just say "i'm having problems". come on dood, dont be a
                 moron.
2025/05/24 [General] UID:1000 Activity:popular
5/24    

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