Dear We have a problems. our router 1721 Fast Ethernet port unstable not work. The port status always show up , but cannot connect to network. We need restart Fast Ethernet mobule , after work on normaly. Because this router managed by ISP provide.The ISP engineer say the siwtch problems. I have replace the cable connect to siwtch,. I want to know error is switch or router. please advice.
Thanks ITITITIT
Ok... This is a WILD guess - Check that the duplex of the switch. The duplex and speed of the switch MUST match the duplex and speed of the router. You can verify if you have the correct duplex by checking the error counters on your switch port. If you have more than just a very few errors, it's most likely wrong. In that case, you'll need to check with your ISP and match yours to theirs.
Does the switch show the router is connected? Send the output of the "show interface" for the interface in question.
JC
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