Description

This article describes the issue of the multicast route frequently disappearing and re-appearing in the multicast network, due to the MTU mismatch on directly connected links.

Symptoms

The multicast route frequently disappears and re-appears in the multicast network, due to the MTU mismatch on directly connected links.

Solution

Different MTU values on directly connected links may cause this random behavior of the multicast traffic in the network.

In the following topology, multicast is running in a stable scenario. Modifications were made to the MTU value the directly connected link's interface, which is between Mayank-M7i and Atlantic-M320 routers. The different MTU value caused various multicast traffic groups to frequently disappear and re-appear.

The PIM protocol does not verify or negotiate the MTU value with its directly connected neighbor; so Atlantis was creating larger PIM packets, based on its larger MTU value on its interface and were not accepted by the Mayank-M7i router. Again, PIM was creating some smaller and larger packets.

So, based on whatever the Mayank-M7i router was able to absorb with its MTU value, it was able to process that and it was not able to process the packets, which were larger than the MTU value of  Mayank-M7i. So, certain groups were working and some were not. Again, this is dynamic behavior; so, it was unpredictable.

Topology :

          Source
         +
         |
         |
         |
     +---+---+                   +-------+
     |       |                   |       |
     |Mayank |                   |Devang |
     | M7i   |                   |M7i RP |
     +---+---+                   +---+---+
         | 002                       |
         | MTU 1518                  |
         |                           |
         |    +------------------+   |
         |    |                  |   |
         +----+    Atlantis      +---+
         215  |   M320           |
     MTU:9192 +--------+---------+
                       |
                       |
                       |
                   +---+---+
                   |       |
                   |Thunder+-------+Receiver
                   | MX    |
                   +-------+




lab@mayank-m7i> show interfaces terse ge-0/0/3                                        
Interface               Admin Link Proto    Local                 Remote
ge-0/0/3                up    up  
ge-0/0/3.0              up    up   inet     172.100.50.1/30 

lab@mayank-m7i> show interfaces terse ge-0/0/2    
Interface               Admin Link Proto    Local                 Remote
ge-0/0/2                up    up  
ge-0/0/2.4              up    up   inet     172.130.40.1/30 
ge-0/0/2.32767          up    up  

lab@mayank-m7i>

lab@mayank-m7i> show interfaces ge-0/0/2 | match mtu            
Link-level type: Ethernet, MTU: 1518, Speed: 1000mbps, 
BPDU Error: None, MAC-REWRITE Error:
 
None, Loopback: Disabled,
 Source filtering: Disabled,
Protocol inet, MTU: 1500

lab@mayank-m7i>

lab@atlantis-M320-re0> show interfaces terse ge-2/1/5  
Interface               Admin Link Proto    Local                 Remote
ge-2/1/5                up    up  
ge-2/1/5.4              up    up   inet     172.130.40.2/30 
                                   multiservice
ge-2/1/5.32767          up    up   multiservice

lab@atlantis-M320-re0>

lab@atlantis-M320-re0> show interfaces ge-2/1/5 | match mtu 
Link-level type: Ethernet, MTU: 9192, Speed: 1000mbps, BPDU Error: None, MAC-REWRITE Error:
None, Loopback: Disabled, Source filtering: Disabled,
    Protocol inet, MTU: 9174
    Protocol multiservice, MTU: Unlimited
    Protocol multiservice, MTU: Unlimited





lab@atlantis-M320-re0> monitor traffic interface ge-2/1/5 size 2000  < running TCP dump on interface connected to Mayank-M7i router.
verbose output suppressed, use  or  for full protocol decode
Address resolution is ON. Use  to avoid any reverse lookup delay.
Address resolution timeout is 4s.
Listening on ge-2/1/5, capture size 2000 bytes

Reverse lookup for 172.130.40.1 failed (check DNS reachability).
Other reverse lookup failures will not be reported.
Use  to avoid reverse lookups on IP addresses.

20:50:18.959687 Out IP truncated-ip - 3180 bytes missing! 172.130.40.2 > 224.0.0.13: 172.130.40.2 > 224.0.0.13:PIMv2, Join / Prune, length 5114  < PIM join/prune packet length is larger then the MTU size of Mayank-M7i router's interface. 
20:50:18.991051 Out IP truncated-ip - 1800 bytes missing! 172.130.40.2 > 224.0.0.13: 172.130.40.2 > 224.0.0.13:PIMv2, Join / Prune, length 3734
20:51:18.962301 Out IP truncated-ip - 3180 bytes missing! 172.130.40.2 > 224.0.0.13: 172.130.40.2 > 224.0.0.13:PIMv2, Join / Prune, length 5114
20:51:18.993112 Out IP truncated-ip - 1800 bytes missing! 172.130.40.2 > 224.0.0.13: 172.130.40.2 > 224.0.0.13:PIMv2, Join / Prune, length 3734
20:51:21.064815 Out IP 172.130.40.2 > 224.0.0.22: igmp v2 report 224.0.0.22
20:51:23.189523 Out IP 172.130.40.2 > 224.0.0.13: 172.130.40.2 > 224.0.0.13:PIMv2, Hello, length 34

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics   < In this command you will observe the zero value of PPS for few multicast groups.
    Statistics: 2 kBps, 40 pps, 27853 packets
    Statistics: 2 kBps, 40 pps, 27845 packets
    Statistics: 2 kBps, 40 pps, 27837 packets
    Statistics: 2 kBps, 40 pps, 27830 packets
    Statistics: 2 kBps, 40 pps, 27824 packets
    Statistics: 2 kBps, 40 pps, 27819 packets
    Statistics: 2 kBps, 40 pps, 27814 packets
    Statistics: 2 kBps, 40 pps, 27851 packets
    Statistics: 2 kBps, 40 pps, 27807 packets
    Statistics: 2 kBps, 40 pps, 27797 packets
    Statistics: 2 kBps, 40 pps, 27793 packets
    Statistics: 2 kBps, 40 pps, 27780 packets
    Statistics: 2 kBps, 40 pps, 27777 packets
    Statistics: 2 kBps, 40 pps, 27777 packets
    Statistics: 2 kBps, 40 pps, 27835 packets
    Statistics: 2 kBps, 40 pps, 27765 packets
    Statistics: 2 kBps, 40 pps, 27760 packets
    Statistics: 2 kBps, 40 pps, 27756 packets
    Statistics: 2 kBps, 40 pps, 27751 packets
    Statistics: 2 kBps, 40 pps, 27745 packets
    Statistics: 2 kBps, 40 pps, 27741 packets
    Statistics: 2 kBps, 40 pps, 27738 packets
    Statistics: 2 kBps, 40 pps, 27734 packets
    Statistics: 2 kBps, 40 pps, 27720 packets
    Statistics: 2 kBps, 40 pps, 27714 packets
    Statistics: 2 kBps, 40 pps, 28941 packets
    Statistics: 2 kBps, 40 pps, 28935 packets
    Statistics: 2 kBps, 40 pps, 28941 packets
    Statistics: 2 kBps, 40 pps, 37977 packets
    Statistics: 2 kBps, 40 pps, 28918 packets
    Statistics: 2 kBps, 40 pps, 28912 packets
    Statistics: 2 kBps, 40 pps, 37994 packets
    Statistics: 2 kBps, 40 pps, 28907 packets
    Statistics: 2 kBps, 40 pps, 28907 packets
    Statistics: 2 kBps, 40 pps, 28871 packets
    Statistics: 2 kBps, 40 pps, 28799 packets
    Statistics: 2 kBps, 40 pps, 28795 packets
    Statistics: 2 kBps, 40 pps, 28782 packets
    Statistics: 2 kBps, 40 pps, 37971 packets
    Statistics: 2 kBps, 40 pps, 38010 packets
    Statistics: 2 kBps, 40 pps, 28783 packets
    Statistics: 2 kBps, 40 pps, 28772 packets
    Statistics: 2 kBps, 40 pps, 28758 packets
    Statistics: 2 kBps, 40 pps, 28752 packets
    Statistics: 2 kBps, 40 pps, 28748 packets
    Statistics: 2 kBps, 40 pps, 28743 packets
    Statistics: 2 kBps, 40 pps, 28732 packets
    Statistics: 2 kBps, 40 pps, 28727 packets
    Statistics: 2 kBps, 40 pps, 27904 packets
    Statistics: 2 kBps, 40 pps, 28721 packets
    Statistics: 2 kBps, 40 pps, 27682 packets
    Statistics: 2 kBps, 40 pps, 28715 packets
    Statistics: 2 kBps, 40 pps, 28713 packets
    Statistics: 2 kBps, 40 pps, 27674 packets
    Statistics: 2 kBps, 40 pps, 37918 packets
    Statistics: 2 kBps, 40 pps, 27666 packets
    Statistics: 2 kBps, 40 pps, 27660 packets
    Statistics: 2 kBps, 40 pps, 27839 packets
    Statistics: 2 kBps, 40 pps, 27644 packets
    Statistics: 2 kBps, 40 pps, 28949 packets
    Statistics: 2 kBps, 40 pps, 27638 packets
    Statistics: 2 kBps, 40 pps, 28946 packets
    Statistics: 2 kBps, 40 pps, 28937 packets
    Statistics: 2 kBps, 40 pps, 27629 packets
    Statistics: 2 kBps, 40 pps, 28929 packets
    Statistics: 2 kBps, 40 pps, 27621 packets
    Statistics: 2 kBps, 40 pps, 27614 packets
    Statistics: 2 kBps, 40 pps, 28923 packets
    Statistics: 2 kBps, 40 pps, 27603 packets
    Statistics: 2 kBps, 40 pps, 27805 packets
    Statistics: 2 kBps, 40 pps, 27596 packets
    Statistics: 2 kBps, 40 pps, 28906 packets
    Statistics: 2 kBps, 40 pps, 28901 packets
    Statistics: 2 kBps, 40 pps, 28898 packets
    Statistics: 2 kBps, 40 pps, 28891 packets
    Statistics: 2 kBps, 40 pps, 28655 packets
    Statistics: 2 kBps, 40 pps, 28647 packets
    Statistics: 2 kBps, 40 pps, 28622 packets
    Statistics: 2 kBps, 40 pps, 28617 packets
    Statistics: 2 kBps, 40 pps, 28616 packets
    Statistics: 2 kBps, 40 pps, 28614 packets
    Statistics: 2 kBps, 40 pps, 28608 packets
    Statistics: 2 kBps, 40 pps, 27848 packets
    Statistics: 2 kBps, 40 pps, 28601 packets
    Statistics: 2 kBps, 40 pps, 28597 packets
    Statistics: 2 kBps, 40 pps, 27562 packets
    Statistics: 2 kBps, 40 pps, 28592 packets
    Statistics: 2 kBps, 40 pps, 28585 packets
    Statistics: 2 kBps, 40 pps, 27834 packets
    Statistics: 2 kBps, 40 pps, 28576 packets
    Statistics: 2 kBps, 40 pps, 28570 packets
    Statistics: 2 kBps, 40 pps, 28565 packets
    Statistics: 2 kBps, 40 pps, 28558 packets
    Statistics: 2 kBps, 40 pps, 28555 packets
    Statistics: 2 kBps, 40 pps, 27538 packets
    Statistics: 2 kBps, 40 pps, 27523 packets
    Statistics: 2 kBps, 40 pps, 28543 packets
    Statistics: 2 kBps, 40 pps, 27505 packets
    Statistics: 2 kBps, 40 pps, 27501 packets
    Statistics: 2 kBps, 40 pps, 28540 packets
    Statistics: 2 kBps, 40 pps, 37859 packets
    Statistics: 2 kBps, 40 pps, 28518 packets
    Statistics: 2 kBps, 40 pps, 27489 packets
    Statistics: 2 kBps, 40 pps, 27467 packets
    Statistics: 2 kBps, 40 pps, 28466 packets
    Statistics: 2 kBps, 40 pps, 27461 packets
    Statistics: 2 kBps, 40 pps, 27455 packets
    Statistics: 2 kBps, 40 pps, 28460 packets
    Statistics: 2 kBps, 40 pps, 28454 packets
    Statistics: 2 kBps, 40 pps, 27439 packets
    Statistics: 2 kBps, 40 pps, 28445 packets
    Statistics: 2 kBps, 40 pps, 27427 packets
    Statistics: 2 kBps, 40 pps, 28435 packets
    Statistics: 2 kBps, 40 pps, 28370 packets
    Statistics: 2 kBps, 40 pps, 27421 packets
    Statistics: 2 kBps, 40 pps, 28421 packets
    Statistics: 2 kBps, 40 pps, 28399 packets
    Statistics: 2 kBps, 40 pps, 27552 packets
    Statistics: 2 kBps, 40 pps, 28402 packets
    Statistics: 2 kBps, 40 pps, 28394 packets
    Statistics: 2 kBps, 40 pps, 27427 packets
    Statistics: 2 kBps, 40 pps, 27416 packets
    Statistics: 2 kBps, 40 pps, 27405 packets
    Statistics: 2 kBps, 40 pps, 28356 packets
    Statistics: 2 kBps, 40 pps, 28348 packets
    Statistics: 2 kBps, 40 pps, 27397 packets
    Statistics: 2 kBps, 40 pps, 28343 packets
    Statistics: 2 kBps, 40 pps, 28338 packets
    Statistics: 2 kBps, 40 pps, 27389 packets
    Statistics: 2 kBps, 40 pps, 27386 packets
    Statistics: 2 kBps, 40 pps, 37778 packets
    Statistics: 2 kBps, 40 pps, 28327 packets
    Statistics: 2 kBps, 40 pps, 27379 packets
    Statistics: 2 kBps, 40 pps, 28315 packets
    Statistics: 2 kBps, 40 pps, 27375 packets
    Statistics: 2 kBps, 40 pps, 28246 packets
    Statistics: 2 kBps, 40 pps, 28239 packets
    Statistics: 2 kBps, 40 pps, 28231 packets
    Statistics: 2 kBps, 40 pps, 27361 packets
    Statistics: 2 kBps, 40 pps, 27347 packets
    Statistics: 2 kBps, 40 pps, 28230 packets
    Statistics: 2 kBps, 40 pps, 28224 packets
    Statistics: 2 kBps, 40 pps, 28218 packets
    Statistics: 2 kBps, 40 pps, 27350 packets
    Statistics: 2 kBps, 40 pps, 27346 packets
    Statistics: 2 kBps, 40 pps, 37949 packets
    Statistics: 2 kBps, 40 pps, 28217 packets
    Statistics: 2 kBps, 40 pps, 28182 packets
    Statistics: 2 kBps, 40 pps, 37940 packets
    Statistics: 2 kBps, 40 pps, 37936 packets
    Statistics: 2 kBps, 40 pps, 37929 packets
    Statistics: 2 kBps, 40 pps, 28185 packets
    Statistics: 2 kBps, 40 pps, 28179 packets
    Statistics: 2 kBps, 40 pps, 37913 packets
    Statistics: 2 kBps, 40 pps, 27498 packets
    Statistics: 2 kBps, 40 pps, 37898 packets
    Statistics: 2 kBps, 40 pps, 37884 packets
    Statistics: 2 kBps, 40 pps, 28163 packets
    Statistics: 2 kBps, 40 pps, 28157 packets
    Statistics: 2 kBps, 40 pps, 37890 packets
    Statistics: 2 kBps, 40 pps, 37713 packets
    Statistics: 2 kBps, 40 pps, 27511 packets
    Statistics: 2 kBps, 40 pps, 37850 packets
    Statistics: 2 kBps, 40 pps, 27489 packets
    Statistics: 2 kBps, 40 pps, 37700 packets
    Statistics: 2 kBps, 40 pps, 27419 packets
    Statistics: 2 kBps, 40 pps, 27472 packets
    Statistics: 2 kBps, 40 pps, 27546 packets
    Statistics: 2 kBps, 40 pps, 27451 packets
    Statistics: 2 kBps, 40 pps, 27750 packets
    Statistics: 2 kBps, 40 pps, 37827 packets
    Statistics: 2 kBps, 40 pps, 27794 packets
    Statistics: 2 kBps, 40 pps, 28028 packets
    Statistics: 2 kBps, 40 pps, 27467 packets
    Statistics: 2 kBps, 40 pps, 37818 packets
    Statistics: 2 kBps, 40 pps, 37801 packets
    Statistics: 2 kBps, 40 pps, 28110 packets
    Statistics: 2 kBps, 40 pps, 37791 packets
    Statistics: 2 kBps, 40 pps, 27523 packets
    Statistics: 2 kBps, 40 pps, 27793 packets
    Statistics: 2 kBps, 40 pps, 28093 packets
    Statistics: 2 kBps, 40 pps, 27442 packets
    Statistics: 2 kBps, 40 pps, 28091 packets
    Statistics: 2 kBps, 40 pps, 37767 packets
    Statistics: 2 kBps, 40 pps, 28083 packets
    Statistics: 2 kBps, 40 pps, 27411 packets
    Statistics: 2 kBps, 40 pps, 37824 packets
    Statistics: 2 kBps, 40 pps, 28053 packets
    Statistics: 2 kBps, 40 pps, 37720 packets
    Statistics: 2 kBps, 40 pps, 28034 packets
    Statistics: 2 kBps, 40 pps, 28044 packets
    Statistics: 2 kBps, 40 pps, 28031 packets
    Statistics: 2 kBps, 40 pps, 28029 packets
    Statistics: 2 kBps, 40 pps, 28028 packets
    Statistics: 2 kBps, 40 pps, 27547 packets
    Statistics: 2 kBps, 40 pps, 37980 packets
    Statistics: 2 kBps, 40 pps, 27953 packets
    Statistics: 2 kBps, 40 pps, 27384 packets
    Statistics: 2 kBps, 40 pps, 37933 packets
    Statistics: 2 kBps, 40 pps, 27368 packets
    Statistics: 2 kBps, 40 pps, 37937 packets
    Statistics: 2 kBps, 40 pps, 27946 packets
    Statistics: 2 kBps, 40 pps, 37839 packets
    Statistics: 2 kBps, 40 pps, 27945 packets
    Statistics: 2 kBps, 40 pps, 37859 packets
    Statistics: 2 kBps, 40 pps, 37787 packets
    Statistics: 2 kBps, 40 pps, 28515 packets
    Statistics: 2 kBps, 40 pps, 27549 packets
    Statistics: 2 kBps, 40 pps, 28513 packets
    Statistics: 2 kBps, 40 pps, 37823 packets
    Statistics: 2 kBps, 40 pps, 37820 packets
    Statistics: 2 kBps, 40 pps, 37766 packets
    Statistics: 2 kBps, 40 pps, 28451 packets
    Statistics: 2 kBps, 40 pps, 28438 packets
    Statistics: 2 kBps, 40 pps, 28369 packets
    Statistics: 2 kBps, 40 pps, 37759 packets
    Statistics: 2 kBps, 40 pps, 27768 packets
    Statistics: 2 kBps, 40 pps, 37805 packets
    Statistics: 2 kBps, 40 pps, 28237 packets
    Statistics: 2 kBps, 40 pps, 28229 packets
    Statistics: 2 kBps, 40 pps, 28228 packets
    Statistics: 2 kBps, 40 pps, 37751 packets
    Statistics: 2 kBps, 40 pps, 28230 packets
    Statistics: 2 kBps, 40 pps, 28224 packets
    Statistics: 2 kBps, 40 pps, 37759 packets
    Statistics: 2 kBps, 40 pps, 28232 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 37763 packets
    Statistics: 2 kBps, 40 pps, 28214 packets
    Statistics: 2 kBps, 41 pps, 28210 packets
    Statistics: 2 kBps, 41 pps, 28357 packets
    Statistics: 2 kBps, 41 pps, 27559 packets
    Statistics: 2 kBps, 40 pps, 28729 packets
    Statistics: 2 kBps, 40 pps, 28169 packets
    Statistics: 2 kBps, 40 pps, 37660 packets
    Statistics: 2 kBps, 40 pps, 37581 packets
    Statistics: 2 kBps, 40 pps, 27466 packets
    Statistics: 2 kBps, 40 pps, 33329 packets
    Statistics: 2 kBps, 40 pps, 28209 packets
    Statistics: 2 kBps, 40 pps, 15585 packets
    Statistics: 2 kBps, 40 pps, 37868 packets
    Statistics: 2 kBps, 40 pps, 28477 packets
    Statistics: 2 kBps, 40 pps, 37817 packets
    Statistics: 2 kBps, 40 pps, 28169 packets
    Statistics: 2 kBps, 40 pps, 37664 packets
    Statistics: 2 kBps, 40 pps, 28580 packets
    Statistics: 2 kBps, 40 pps, 27864 packets
    Statistics: 2 kBps, 40 pps, 28187 packets
    Statistics: 2 kBps, 40 pps, 28085 packets
    Statistics: 2 kBps, 40 pps, 27861 packets
    Statistics: 2 kBps, 40 pps, 28145 packets
    Statistics: 2 kBps, 40 pps, 28139 packets
    Statistics: 2 kBps, 40 pps, 25521 packets
    Statistics: 2 kBps, 40 pps, 28172 packets
    Statistics: 0 kBps, 0 pps, 8401 packets
    Statistics: 2 kBps, 40 pps, 389 packets
    Statistics: 2 kBps, 40 pps, 28083 packets
    Statistics: 2 kBps, 40 pps, 37965 packets
    Statistics: 0 kBps, 0 pps, 8401 packets
    Statistics: 2 kBps, 40 pps, 1444 packets
    Statistics: 2 kBps, 40 pps, 650 packets
    Statistics: 2 kBps, 40 pps, 17103 packets
    Statistics: 2 kBps, 40 pps, 28006 packets
    Statistics: 2 kBps, 40 pps, 31978 packets
    Statistics: 2 kBps, 40 pps, 37903 packets
    Statistics: 2 kBps, 40 pps, 992 packets
    Statistics: 2 kBps, 40 pps, 28077 packets
    Statistics: 2 kBps, 40 pps, 52383 packets
    Statistics: 2 kBps, 40 pps, 3473 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 22288 packets
    Statistics: 2 kBps, 40 pps, 28219 packets
    Statistics: 2 kBps, 40 pps, 28081 packets
    Statistics: 2 kBps, 40 pps, 6119 packets
    Statistics: 2 kBps, 40 pps, 37651 packets
    Statistics: 2 kBps, 40 pps, 8016 packets
    Statistics: 2 kBps, 40 pps, 37817 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 37736 packets
    Statistics: 0 kBps, 0 pps, 8400 packets
    Statistics: 2 kBps, 40 pps, 642 packets
    Statistics: 2 kBps, 40 pps, 8070 packets
    Statistics: 2 kBps, 40 pps, 1511 packets
    Statistics: 2 kBps, 40 pps, 6119 packets
    Statistics: 2 kBps, 40 pps, 2503 packets
    Statistics: 2 kBps, 40 pps, 52277 packets
    Statistics: 2 kBps, 40 pps, 27973 packets
    Statistics: 0 kBps, 0 pps, 8402 packets
    Statistics: 0 kBps, 0 pps, 8400 packets
    Statistics: 2 kBps, 40 pps, 37676 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 32987 packets
    Statistics: 2 kBps, 40 pps, 2662 packets
    Statistics: 2 kBps, 40 pps, 52213 packets
    Statistics: 2 kBps, 40 pps, 15720 packets
    Statistics: 2 kBps, 40 pps, 992 packets
    Statistics: 2 kBps, 40 pps, 27972 packets
    Statistics: 2 kBps, 40 pps, 28424 packets
    Statistics: 2 kBps, 40 pps, 993 packets
    Statistics: 0 kBps, 0 pps, 8399 packets      < highlighted few groups reporting zero value.     You can find number of different groups reporting 0 value in stats.
    Statistics: 0 kBps, 0 pps, 8401 packets
    Statistics: 2 kBps, 40 pps, 994 packets
    Statistics: 0 kBps, 0 pps, 8401 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 11674 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 27949 packets
    Statistics: 0 kBps, 0 pps, 8397 packets
    Statistics: 0 kBps, 0 pps, 8401 packets
    Statistics: 2 kBps, 40 pps, 33358 packets
    Statistics: 2 kBps, 40 pps, 4699 packets
    Statistics: 2 kBps, 40 pps, 15685 packets
    Statistics: 2 kBps, 40 pps, 25870 packets
    Statistics: 2 kBps, 40 pps, 1742 packets
    Statistics: 0 kBps, 0 pps, 8397 packets
    Statistics: 2 kBps, 40 pps, 52385 packets
    Statistics: 2 kBps, 40 pps, 6121 packets
    Statistics: 0 kBps, 0 pps, 8402 packets
    Statistics: 2 kBps, 40 pps, 4685 packets
    Statistics: 0 kBps, 0 pps, 8402 packets
    Statistics: 2 kBps, 40 pps, 25548 packets
    Statistics: 0 kBps, 0 pps, 8401 packets
    Statistics: 2 kBps, 40 pps, 28800 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 0 kBps, 0 pps, 8402 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 986 packets
    Statistics: 2 kBps, 40 pps, 6121 packets
    Statistics: 2 kBps, 40 pps, 988 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 2 kBps, 40 pps, 1729 packets
    Statistics: 0 kBps, 0 pps, 8402 packets
    Statistics: 2 kBps, 40 pps, 988 packets
    Statistics: 0 kBps, 0 pps, 8400 packets
    Statistics: 2 kBps, 40 pps, 988 packets
    Statistics: 0 kBps, 0 pps, 8400 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 0 kBps, 0 pps, 8400 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 1708 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 2 kBps, 40 pps, 988 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 988 packets
    Statistics: 2 kBps, 40 pps, 988 packets
    Statistics: 2 kBps, 40 pps, 5946 packets
    Statistics: 2 kBps, 40 pps, 988 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 988 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 6121 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 5925 packets
    Statistics: 2 kBps, 40 pps, 986 packets
    Statistics: 0 kBps, 0 pps, 8403 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 2 kBps, 40 pps, 989 packets
    Statistics: 2 kBps, 40 pps, 989 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 4664 packets
    Statistics: 2 kBps, 40 pps, 1674 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 989 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 2 kBps, 40 pps, 1642 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 1632 packets
    Statistics: 2 kBps, 40 pps, 51974 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 2 kBps, 40 pps, 989 packets
    Statistics: 2 kBps, 40 pps, 989 packets
    Statistics: 2 kBps, 40 pps, 989 packets
    Statistics: 2 kBps, 40 pps, 989 packets
    Statistics: 2 kBps, 40 pps, 989 packets
   Statistics: 2 kBps, 40 pps, 1617 packets
    Statistics: 2 kBps, 40 pps, 4645 packets
    Statistics: 2 kBps, 40 pps, 6122 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 990 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 2 kBps, 40 pps, 990 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 0 kBps, 0 pps, 8399 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 0 kBps, 0 pps, 8392 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 990 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 2 kBps, 40 pps, 2577 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 2 kBps, 40 pps, 990 packets
    Statistics: 0 kBps, 0 pps, 8400 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 0 kBps, 0 pps, 8398 packets
    Statistics: 2 kBps, 40 pps, 987 packets
    Statistics: 2 kBps, 40 pps, 6123 packets
    Statistics: 2 kBps, 40 pps, 988 packets

MASTER

Variation in number of multicast group counter in our lab:

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 405 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 405 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 424 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 424 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 424 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 318 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 318 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 419 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 417 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 417 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 417 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 417 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 417 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 426 lines

MASTER
lab@Thunder> show multicast route logical-system lr2 extensive | match statistics | count    
Count: 432 lines