Pause input and flow control

Unanswered Question
Sep 27th, 2007
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I am having issue on my 3750G gig interface, it is not passing data more than 200M.Some how its giving me lots of input Pause on both sides,can some one explain if there is congesstion issue,do I need to enable flow control on both sides?


-1#sh interface GigabitEthernet1/0/25

GigabitEthernet1/0/25 is up, line protocol is up (connected)

Hardware is Gigabit Ethernet, address is 0019.2f7f.5919 (bia 0019.2f7f.5919)

Description: LES link to TeleHouse

MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,

reliability 255/255, txload 1/255, rxload 17/255

Encapsulation ARPA, loopback not set

Keepalive not set

Full-duplex, 1000Mb/s, link type is force-up, media type is 1000BaseSX SFP

input flow-control is off, output flow-control is unsupported <----------------------?

ARP type: ARPA, ARP Timeout 04:00:00

Last input never, output 00:00:58, output hang never

Last clearing of "show interface" counters never

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 69442000 bits/sec, 22986 packets/sec

5 minute output rate 0 bits/sec, 0 packets/sec

2039460396 packets input, 1512854019 bytes, 0 no buffer

Received 11 broadcasts (0 multicast)

0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog, 0 multicast, 124553349 pause input <--------------------issue ?

0 input packets with dribble condition detected

208502459 packets output, 2269043255 bytes, 0 underruns

0 output errors, 0 collisions, 3 interface resets

0 babbles, 0 late collision, 0 deferred

0 lost carrier, 0 no carrier, 0 PAUSE output

0 output buffer failures, 0 output buffers swapped

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Danilo Dy Thu, 09/27/2007 - 05:54
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The interface keepalive is not set. Your interface maybe up/up but it could be spoofing. Set the interface keepalive to 10 seconds



mohammedrafiq Thu, 09/27/2007 - 07:25
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thanks,I will set the keepalive to 10 sec, but the interface is always up and passing data all the time, I am worried why its showing lots of input pause ?


vijayasankar Sun, 09/30/2007 - 23:05
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Let us know what is connected to this gig interface.

To slow down the received traffic rate, that end device is sending the pause signal to this port, indicating the port to slow down/pause the traffic.

There is nothing wrong with this switch port. Enable the input flow control at this port if possible and observe the results.

Hope this helps.



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