05-20-2013 10:03 AM - edited 03-07-2019 01:27 PM
hi ,
i noticed the "output drops" increasing in interface gi 1/0/1 in my switch 2960-S although the utilization of my interface is between 20% and 50 %
SW__A#sh interfaces gigabitEthernet 1/0/1
GigabitEthernet1/0/1 is up, line protocol is up (connected)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 93/255, rxload 3/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 1000Mb/s, media type is 10/100/1000BaseTX
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 00:10:00
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 78484
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 14786000 bits/sec, 22426 packets/sec
30 second output rate 365630000 bits/sec, 42896 packets/sec
6584758 packets input, 575696417 bytes, 0 no buffer
SW__A#sh controllers gigabitEthernet 1/0/1 utilization
Receive Bandwidth Percentage Utilization : 3
Transmit Bandwidth Percentage Utilization : 50
SW_A#sh interfaces gigabitEthernet 1/0/1 | include Total output drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 585722
SW_A#sh controllers gigabitEthernet 1/0/1 utilization
Receive Bandwidth Percentage Utilization : 1
Transmit Bandwidth Percentage Utilization : 24
The IOS version is :
Switch Ports Model SW Version SW Image
------ ----- ----- ---------- ----------
* 1 28 WS-C2960S-24TD-L 12.2(55)SE5 C2960S-UNIVERSALK9-M
what is the cause of this issue ??
thank you
05-20-2013 03:31 PM
Even if the other switch is sending pause frames, the 2960S is ignoring them,
Good point, Paolo.
05-20-2013 03:40 PM
Ok , thank you for all this explanation
so it 's possible to enable flow-control in the switch 2960s ?
thank you ,
05-20-2013 04:03 PM
hi ,
i have found it
interface Gi 1/0/1
flowcontrol receive on
flowcontrol send on
i will test that and i will send to you the result
thank you
05-21-2013 01:06 PM
Hi ,
when i activate "flowcontrol " on the interface ( by the command flowcontrol receive on) i noticed that the interfaces of the router ( ASR-1001) conneceted to this Switch Become "shut down " !!!!
I did not understand why??? !!
05-21-2013 01:10 PM
It doesn't really matter, as flow control does not help at in case of output drops.
05-20-2013 05:55 PM
Hi ,
Yes the qos is disabled in the switch.
Sent from Cisco Technical Support Android App
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