In order to display the ELAM results, enter the show dbus and show rbus commands. If there is
a high volume of traffic that matches the same triggers, the DBUS and RBUS might trigger on
different frames. Therefore, it is important to check the internal sequence numbers on the DBUS
and RBUS data in order to ensure that they match:
module-4(f4-l2-elam)# show dbus | i seq
port-id : 0x0 sequence-number : 0x868
module-4(f4-l2-elam)# show rbus | i seq
de-bri-rslt-valid : 0x1 sequence-number : 0x868
Here is the excerpt from the ELAM data that is most relevant to this example (some output is
omitted):
module-4(f4-l2-elam)# show dbus
--------------------------------------------------------------------
LBD IPV4
--------------------------------------------------------------------
ttl : 0xff l3-packet-length : 0x54
destination-address: 10.0.3.101
source-address: 10.0.5.101
--------------------------------------------------------------------
packet-length : 0x66 vlan : 0x9c4
segid-lsb : 0x0 source-index : 0xe05
destination-mac-address : 8c60.4f07.ac65
source-mac-address : 8c60.4fb7.3dc2
port-id : 0x0 sequence-number : 0x868
module-4(f4-l2-elam)# show rbus
--------------------------------------------------------------------
L2 RBUS RSLT CAP DATA
--------------------------------------------------------------------
de-bri-rslt-valid : 0x1 sequence-number : 0x868
vlan : 0x37 rbh : 0x65
cos : 0x0 destination-index : 0x9ed
With the DBUS data, you can verify that the frame is received on VLAN 2500 with a source MAC
address of 8c60.4fb6.3dc2 and a destination MAC address of 8c60.4f07.ac65. You can also see
that this is an IPv4 frame that is sourced from 10.0.5.101, and is destined to 10.0.3.101.
Tip: There are several other useful fields that are not included in this output, such as Type of
Service (TOS) value, IP flags, IP length, and L2 frame length.
In order to verify on which port the frame is received, enter the SRC_INDEX command (the source
Local Target Logic (LTL)). Enter this command in order to map an LTL to a port or group of ports
for the N7K:
N7700# show system internal pixm info ltl 0xe05
Member info
------------------
Type LTL
---------------------------------
PHY_PORT Eth4/1
FLOOD_W_FPOE 0xc031
The output shows that the SRC_INDEX of 0xe05 maps to port Eth4/1. This confirms that the
frame is received on port Eth4/1.
With the RBUS data, you can verify that the frame is routed to VLAN 55. Notice that the TTL starts
as 0xff in the DBUS data. Additionally, you can confirm the egress port from the DEST_INDEX