Droped packets but Tx/RX show 1/255

Jason Jackal · ‎11-25-2014

Folks:

I am trying to determine a few issues with my interfaces and servers. Interface example

GigabitEthernet2/28 is up, line protocol is up (connected
reliability 255/255, txload 1/255, rxload 1/255
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 6431978

@02:42

GigabitEthernet2/28 is up, line protocol is up (connected
reliability 255/255, txload 1/255, rxload 1/255
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 6433679

What is odd - I am not seeing any change in Tx/RX values; however, with in 1/2 minutes I am seeing 'Total output drops:' increase when I pull stats via 'sh int'. In addition, I am not seeing input queue drops.

What methods would I use to check why packets are being dropped when the Tx/Rx load is in a normal range?

thank you

/JJ/

InayathUlla Sharieff · ‎11-25-2014

show version ?

Wht is connected to this port?

Jason Jackal · ‎11-25-2014

Switch is a 6513

and a HP switch is connected to the interface; however, I do not have access to this device to pull details... that is another department.

Joseph W. Doherty · ‎11-25-2014

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Normally, packets are dropped when queues overflow. This can happen even with very low load averages (the important term being "average"). Microbursts can cause such.

Also 6500 line cards, including gig, come in many "flavors". Some of the older cards have multiple ports that share egress buffers, so your egress drops might not even be due to traffic on your port.