[PTX ] What does ‘iq_disabled_drop’ messages mean?

Description

The iq_disabled_drop messages on a PTX can be cosmetic and should be ignored. These messages may appear when 10GE PIC is in use.

Symptoms

The iq_disabled_drop messages may appear when an interface without configuration on a 10GE PIC continuously receives any kind of packet.

Snippet of log message:

router-re0 : %PFE-6: fpc4 INTR: throttle 3630sec PIC-4/0 TLCHIP[0]:tl.ipw[0].intr.status:iq_disabled_drop(0): (Count:907624)
router-re0 : %PFE-6: fpc4 INTR: throttle 3600sec PIC-4/0 TLCHIP[0]:tl.ipw[0].intr.status:iq_disabled_drop(0): (Count:911254)
router-re0 : %PFE-6: fpc4 INTR: throttle 3630sec PIC-4/0 TLCHIP[0]:tl.ipw[0].intr.status:iq_disabled_drop(0): (Count:914914)
router-re0 : %PFE-6: fpc4 INTR: throttle 3600sec PIC-4/0 TLCHIP[0]:tl.ipw[0].intr.status:iq_disabled_drop(0): (Count:918544)
router-re0 : %PFE-6: fpc4 INTR: throttle 3630sec PIC-4/0 TLCHIP[0]:tl.ipw[0].intr.status:iq_disabled_drop(0): (Count:922204)
router-re0 : %PFE-6: fpc4 INTR: throttle 3600sec PIC-4/0 TLCHIP[0]:tl.ipw[0].intr.status:iq_disabled_drop(0): (Count:925834)

The above log message shows the drop count is increasing. Users may confirm this counter with the Junos command, show pfe statistics error .

 show pfe statistics error 
 --- snip --- 
 Slot 4 
 
 pic slot 0 port iq_disable_drop counts: 
 port 0: 0; port 1: 0; port 2: 0; port 3: 0; 
 port 4: 0; port 5: 0; port 6: 0; port 7: 0; 
 port 8: 0; port 9: 0; port10: 0;  port11: 3810996;  
 port12: 0; port13: 0; port14: 0; port15: 0; 
 port16: 0; port17: 0; port18: 0; port19: 0; 
 port20: 0; port21: 0; port22: 0; port23: 0; 
 --- snip ---

In the above example, et-4/0/11 detects iq_disable_drop . This counter indicates dropped packets at TL chip on which the port hosts.

Solution

The message appears when an interface with default configuration (i.e. no configuration is done) on 10 GE PIC continuously receives a packet. The message can be stopped by adding a unit or setting it disable to the interface. It would be preferable to disable the interface if it is not in use.

   set interfaces et-X/X/X unit X
   OR
   set interfaces et-X/X/X disable

Sample pattern in product network:

    detect iq_disable_drop 
                    <------------------ARP, OSPF hello 
    +--------------+                           +--------------+ 
    |   PTX3000    |                           |    Remote    | 
    |    [DUT]     |---------------------------|    Device    | 
    |              |A                         A|              | 
    +--------------+|                         |+--------------+ 
                    |                         | 
                 no config                IP address 
                                             OSPF

Reference Tests

The following tests are references of ‘iq_disable_drop’ traffic. These tests show that any traffic will trigger the message.

Test topology

                    <-----------------------Test traffic(100pps*10sec) 
    +--------------+                           +--------------+ 
    |    PTX3000   |et-4/0/11                  |    Tester    | 
    |              |---------------------------|              | 
    |              |                           |              | 
    +--------------+                           +--------------+ 
         PIC: 24x 10GE(LAN) SFP+ 
         MAC: 00:AA:AA:AA:AA:AA

1. Unicast traffic with valid MAC address.

    Test traffic 
    destination MAC       : 00:AA:AA:AA:AA:AA 
    source MAC            : 00:BB:BB:BB:BB:BB 
    destination ip address: 10.0.0.2 
    source ip address     : 10.0.0.1

    show pfe statistics error 
    --- snip --- 
    Slot 4 
 
    pic slot 0 port iq_disable_drop counts: 
    port 0: 0; port 1: 0; port 2: 0; port 3: 0; 
    port 4: 0; port 5: 0; port 6: 0; port 7: 0; 
    port 8: 0; port 9: 0; port10: 0;  port11: 1000;  
    port12: 0; port13: 0; port14: 0; port15: 0; 
    port16: 0; port17: 0; port18: 0; port19: 0; 
    port20: 0; port21: 0; port22: 0; port23: 0; 
    --- snip ---

2. Unicast traffic with invalid MAC address.

    Test traffic 
    destination MAC       : 00:CC:CC:CC:CC:CC 
    source MAC            : 00:BB:BB:BB:BB:BB 
    destination ip address: 10.0.0.2 
    source ip address     : 10.0.0.1

    show pfe statistics error 
    --- snip --- 
    Slot 4 
 
    pic slot 0 port iq_disable_drop counts: 
    port 0: 0; port 1: 0; port 2: 0; port 3: 0; 
    port 4: 0; port 5: 0; port 6: 0; port 7: 0; 
    port 8: 0; port 9: 0; port10: 0;  port11: 1000;  
    port12: 0; port13: 0; port14: 0; port15: 0; 
    port16: 0; port17: 0; port18: 0; port19: 0; 
    port20: 0; port21: 0; port22: 0; port23: 0; 
    --- snip ---

3. Multicast traffic.

    Test traffic 
    destination MAC : 01:00:5E:01:01:01 
    source MAC : 00:BB:BB:BB:BB:BB 
    destination ip address: 224.1.1.1 
    source ip address : 10.0.0.1

    show pfe statistics error 
    --- snip --- 
    Slot 4 
 
    pic slot 0 port iq_disable_drop counts: 
    port 0: 0; port 1: 0; port 2: 0; port 3: 0; 
    port 4: 0; port 5: 0; port 6: 0; port 7: 0; 
    port 8: 0; port 9: 0; port10: 0;  port11: 1000;  
    port12: 0; port13: 0; port14: 0; port15: 0; 
    port16: 0; port17: 0; port18: 0; port19: 0; 
    port20: 0; port21: 0; port22: 0; port23: 0; 
    --- snip ---

4. Broadcast traffic.

    Test traffic 
    destination MAC : FF:FF:FF:FF:FF:FF 
    source MAC : 00:BB:BB:BB:BB:BB 
    destination ip address: 10.0.0.255 
    source ip address : 10.0.0.1 
 
    show pfe statistics error 
    --- snip --- 
    Slot 4 
 
    pic slot 0 port iq_disable_drop counts: 
    port 0: 0; port 1: 0; port 2: 0; port 3: 0; 
    port 4: 0; port 5: 0; port 6: 0; port 7: 0; 
    port 8: 0; port 9: 0; port10: 0;  port11: 1000;  
    port12: 0; port13: 0; port14: 0; port15: 0; 
    port16: 0; port17: 0; port18: 0; port19: 0; 
    port20: 0; port21: 0; port22: 0; port23: 0; 
    --- snip ---