Reset Ports Cisco Catalyst Switch: Resetting And Troubleshooting Interface Problems

I have a server connected to a cisco switch. Actually it's a Cisco Catalyst® 4000 Series modular switch, the line includes the Cisco Catalyst 4003 and Catalyst 4006 chassis.

I've been asked to reset this port on the switch because the server is having extremely slow downloads... The server actually has two nics and they are plugged into 3/44 and 3/45.

Cisco - Troubleshooting Switch Port and Interface Problems
Cisco - Troubleshooting Cisco Catalyst Switches to NIC Compatibility Issues

So if I know the port:

switch2#show interfaces fastEthernet 3/45
FastEthernet3/45 is up, line protocol is up (connected)
Hardware is Fast Ethernet Port, address is 000d.28c0.5a6c (bia 000d.28c0.5a6
Description: server50 - nic2
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 251/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Half-duplex, 100Mb/s
input flow-control is unsupported output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters 18w4d
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 7000 bits/sec, 9 packets/sec
5 minute output rate 16000 bits/sec, 9 packets/sec
185836 packets input, 26093123 bytes, 0 no buffer
Received 4945 broadcasts (6 multicast)
0 runts, 0 giants, 0 throttles
1 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
961576 packets output, 303350470 bytes, 0 underruns
26636 output errors, 572 collisions, 0 interface resets
0 babbles, 26040 late collision, 0 deferred
1 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

So we're going to enter the configuration mode:
switch2#config t

specify the interface:

switch2(config)#interface fastEthernet 3/44

Shut it down:

switch2(config-if)#shut

Jump over to the other interface:

switch2(config)#interface fastEthernet 3/45

Shut it down:

switch2(config-if)#shut

No shut it:
switch2(config-if)#no shut

Jump Back to the first Interface:

switch2(config)#interface fastEthernet 3/44

No shut it:
switch2(config-if)#no shut

Exit Interface Mode:
switch2(config-if)#exit

Exit Configure Terminal Mode:
switch2(config)#exit

Let's take a look at that interface:
switch2#sh inter fastEthernet 3/45
FastEthernet3/45 is up, line protocol is up (connected)
Hardware is Fast Ethernet Port, address is 000d.28c0.5a6c (bia 000d.28c0.5a6
Description: server50 - nic2
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 251/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Half-duplex, 100Mb/s
input flow-control is unsupported output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters 18w4d
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 7000 bits/sec, 9 packets/sec
5 minute output rate 16000 bits/sec, 9 packets/sec
185836 packets input, 26093123 bytes, 0 no buffer
Received 4945 broadcasts (6 multicast)
0 runts, 0 giants, 0 throttles
1 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
961576 packets output, 303350470 bytes, 0 underruns
26636 output errors, 572 collisions, 0 interface resets
0 babbles, 26040 late collision, 0 deferred
1 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

Notice that port is set to 100 half!

So let's change that:

switch2#config t
switch2(config)#interface fast 3/45
switch2(config-if)#duplex full
switch2(config-if)#end
switch2#show int fast 3/45
FastEthernet3/45 is up, line protocol is up (connected)
Hardware is Fast Ethernet Port, address is 000d.28c0.5a6c (bia 000d.28c0.5a6c)
Description: server50 - nic2
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s
input flow-control is unsupported output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters 18w5d
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
193982 packets input, 27098681 bytes, 0 no buffer
Received 5910 broadcasts (6 multicast)
0 runts, 0 giants, 0 throttles
1 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
1113726 packets output, 315567784 bytes, 0 underruns
26822 output errors, 579 collisions, 0 interface resets
0 babbles, 26218 late collision, 0 deferred
1 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

Looks like a lot of errors!

Let's clear the counters!


switch2#clear counters fast 3/45
Clear "show interface" counters on this interface [confirm]
switch2#show int fast 3/45
FastEthernet3/45 is up, line protocol is up (connected)
Hardware is Fast Ethernet Port, address is 000d.28c0.5a6c (bia 000d.28c0.5a6c)
Description: server50 - nic2
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s
input flow-control is unsupported output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters 00:00:04
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
6 packets output, 384 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out


We need to identify the MAC address of that NIC and send it to server support!

switch2#sh mac-address-table interface fastEthernet 3/45
Unicast Entries
vlan mac address type protocols port
-------+---------------+--------+---------------------+--------------------
415 0012.3f21.d433 dynamic ip FastEthernet3/45

There you go, tell the server support team to reseat that nic... if that doesn't fix, it sounds like it needs replaced.
Keywords: Reset Ports Cisco Catalyst Switch: Resetting And Troubleshooting Interface Problems