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New Member

Cat1900 drops network traffic.

Hi all. I have a Catalyst 1900 behind a 1750 router. Users complain about their applications being dropped throughout the day. The switch doesn't stop responding to ping. The users usually reboot their computers and the issue is resolved. Could this be a flapping port?

The weird thing is port 0/8 shows up, but does not show up as plugged in when using the show mac-addresst table. Can anyone help me troubleshoot this issue?


0001.422C.75E8 Ethernet 0/10 Dynamic All

0008.7430.1CB8 Ethernet 0/15 Dynamic All

0006.5B6F.EA74 Ethernet 0/5 Dynamic All

000B.DB41.141C Ethernet 0/4 Dynamic All

00B0.D008.942D Ethernet 0/3 Dynamic All

0040.2B60.E195 Ethernet 0/6 Dynamic All

0030.C153.BDBC Ethernet 0/1 Dynamic All

0030.C154.724B Ethernet 0/2 Dynamic All

New Member

Re: Cat1900 drops network traffic.

Ethernet 0/8 is Suspended-no-linkbeat

Hardware is Built-in 10Base-T

Address is 0003.6BFB.7748

MTU 1500 bytes, BW 10000 Kbits

802.1d STP State: Forwarding Forward Transitions: 1

Port monitoring: Disabled

Unknown unicast flooding: Enabled

Unregistered multicast flooding: Enabled


Duplex setting: Half duplex

Back pressure: Disabled


Receive Statistics Transmit Statistics

------------------------------------- -------------------------------------

Total good frames 578795 Total frames 861014

Total octets 187641983 Total octets 623904478

Broadcast/multicast frames 10826 Broadcast/multicast frames 227775

Broadcast/multicast octets 1491369 Broadcast/multicast octets 16695674

Good frames forwarded 578795 Deferrals 1196

Frames filtered 0 Single collisions 5067

Runt frames 2 Multiple collisions 5107

No buffer discards 0 Excessive collisions 0

Queue full discards 0

Errors: Errors:

FCS errors 0 Late collisions 0

Alignment errors 4 Excessive deferrals 333

Giant frames 4 Jabber errors 0

Address violations 0 Other transmit errors 0