[MX] The command 'show services accounting flow' returns no output for RE based jflow (v5 and v8)

Summary:

It is expected behavior for 'show services accounting flow' to not return any output when using routing engine (RE) based jflow (v5 and v8). The MS-PIC based jflow (v5 and v8) will not be affected.

Symptoms:

Example output of MS-PIC based jflow (v5 and v8):

user@host>show services accounting flow

Service Accounting interface: rsp0, Local interface index: 171
Service name: (default sampling)
Interface state: Accounting
  Flow information
    Flow packets: 87168293, Flow bytes: 5578770752
    Flow packets 10-second rate: 45762, Flow bytes 10-second rate: 2928962
    Active flows: 1000, Total flows: 2000
    Flows exported: 19960, Flows packets exported: 582
    Flows inactive timed out: 1000, Flows active timed out: 29000

The output of RE based jflow(v5 and v8):

user@host> show services accounting flow
<<<<<<< no output >>>>>>>

Cause:

The function of obtaining 'show services accounting flow' output is provided by MS-PIC. RE based flow does not use MX-PIC to do sampling, so this command can not get any output

Solution:

Although we cannot get 'show services accounting flow' output when using RE based flow, we can get the flow record by using monitor traffic interface.

Example:

lab@mx480-re0> show firewall
Filter: IPv4-sample
Counters:
Name Packets
flowv5                     7323 <--- flow packets increasing

lab@mx480-re0> monitor traffic interface ge-2/0/5.0 no-resolve size 1500 matching "port 2055" extensive <--- we can see flow record below                                      
Address resolution is OFF.
Listening on ge-2/0/5.0, capture size 1500 bytes
09:42:22.129714 Out
        Juniper PCAP Flags [Ext], PCAP Extension(s) total length 16
          Device Media Type Extension TLV #3, length 1, value: Ethernet (1)
          Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14)
          Device Interface Index Extension TLV #1, length 2, value: 185
          Logical Interface Index Extension TLV #4, length 4, value: 141073
        -----original packet-----
        0c:86:10:23:13:99 > 00:14:f6:26:e0:1f, ethertype IPv4 (0x0800), length 114: (tos 0x0, ttl  64, id 46827, offset 0, flags [none], proto: UDP (17), length: 100) 2.2.2.2.54685 > 200.0.0.2.2055: [udp sum ok] UDP, length 72

Knowledge Base