All language subtitles for 4. Speed & Duplex Demo Fix Issue between router and switch

So let’s fix this problem between router 1 and 2950-1.

So on the router it’s currently configured to use a speed of 100.

So I’m going to set the speed to auto.

This router doesn’t give me the option to set duplex.

So show run int f/0 speed is auto sh int f/0 speed is still half duplex.

The router can’t negotiate with the switch.

So once again it moves to a full back position of 10 meg half duplex.

and this is what has cause a lot of problem in the past because the 1 side

such as the router can’t negotiate with the other side, it simply moves to the
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lowest possible speed which is half duplex 10 Mbps where's the switch is using full duplex.
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So on this switch sh run int f0/3, speed is 10, duplex is full
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let’s change that to speed rather speed auto, duplex auto, sh run int f0/3 no configuration
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sh int f0/3 notice it is now using 100 meg full duplex and on the router
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we are getting 100 meg full duplex, so thats a lot better.
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The router and the switch have negotiated correctly to use 100 Mbps full duplex.
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So can we ping router 2? Yes we can.
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Let’s do a large ping, large datagram size, pings are being sent without any problems
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we're not seeing any late collisions at the moment because the speed and duplex have
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negotiated properly, this may indicate a problem somewhere else in the network.
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At the moment every things looks good, sh int f0
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Now we still see late collisions but that’s because of the previous counters.
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So I’m gonna clear the counters and then do the command sh int f0 again.
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And notice you see 0 late collisions.
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So when looking at your output be careful of the information.
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Clear counters and we could specify a specific interface.
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Allows us to clear the counters on that interface
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so that we see fresh information
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So once again if we ping 10.1.1.2 1000 pings.
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Large packet size, we're sending some traffic on this side, sh int f0/3
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we’ve got the input errors and CRC's
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so clear counters f0/3 we don’t see any input errors and CRC's.
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Obviously you need to monitor that over period of time
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so we are seeing a certain number of packets in and certain number of packet out.
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So traffic is definitely being sent and received on this interface.
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We're not seeing any input errors which is better than we saw last time
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but you just need to monitor that for a period of time
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on the routers sh int f0 we see the number of packets input
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number of packets output. we have no late collision at the moment.
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So that's a lot better than what we saw previously.
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Now on this switch we're still seeing another problem with the duplex mismatch to switch 2.
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So this connection here has a duplex problem.