Eth-trunk interface does not support random packet sampling problem

Handling Process

1.Firstly,We check sampling configuration is complete.configuration include sampling ratio, host and source address, configure sampling mode in slot view, enable sampling in interface view.

#

IP netstreamas - mode 32

IP netstreamexportversion9origin - as BG P - nexthop

IP netstreamsampler RAN dom, packets 100 inbound

IP netstreamsampler RAN dom, packets 100 outbound

IP netstreamexportsource 172.3.1.1

IP netstreamexporthost 172.3.2.6 9905

#

InterfaceEth - Trunk8. 103

Vlan - type dot1q 103

...

IP netstreaminbound

#

Slot 3

IP netstreamsamplertoslotself

#


2. To compare and ***yze  other sampling configuration of interface.

other sampling configuration is shown below

#

Interface GigabitEthernet2 / 0/4

Undoshu TD own

Mtu 1550

...
IP netstreaminbound

IP netstreamstatisticsenable

#

After inquiry,sampling information can be collected in slot2.

[RST-ISP - AGG -06 -diagnose ] dis IP NetStream Cache Asslot2

Starttoshowinformationofaggregation - ascacheofslot 2

Gettinguserdatafromcachesuccess.



DstIf DstAs Streams Packets Direction

SrcIf SrcAs

,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,


108 /0/0 36351 One 2. In

GI2 and 0/4 132032


108 and 1/0 45758 Three 135 In

GI2 and 0/4 132032


108 and 1/0 1267 One One In

GI2 and 0/4 132032


108 /0/0 18837 2. 2. In

GI2 and 0/4 132032


108 and 1/0 56041 Three Three In

GI2 and 0/4 132032


108 /0/0 48882 One One In

GI2 and 0/4 132032

...


After analysis,sampling information cannot be colleced in et-trunk and sampling mode is random packet sampling.

After analysis and confirmation,Eth-trunk only support fixed packet sampling.

fixed package sampling command:

IP netstreamsamplerfix - packets Fix, packet - number { Inbound | Outbound }

Root Cause

Eth-trunk does not support random packet sampling.
Solution

【Resolution Summary】
【Resolution Details】
Sampling mode change to fixed package sampling to slove the problem.
Whatever sampling mode, only sampling way is different.packet size is random in live network and two ways does not differ much.
Suggestions

1. Eth-trunk/ip-trunk /tunnel /mtunel only Support  fixed package sampling.
2.  Physical port and  logical port  are only Support fixed package sampling in LPUF-20/21/40 Board.
equipment support four simpling mode: fixed packet sampling, random packet sampling, fixed interval sampling and random interval sampling,
so we should  set a proper sampling mode to suit your need.