docs: add useful debug CLI

Change-Id: I5ef9ecd741f1623ae1b7a23fa0a4fa6db7e243a3
Signed-off-by: Scott Keeler <skeeler@cisco.com>
diff --git a/docs/reference/cmdreference/show/show.rst b/docs/reference/cmdreference/show/show.rst
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+.. _interface:
+
+.. toctree::
+
+.. note:: For a complete list of CLI Debug commands refer to the Debug CLI section of the `Source Code Documents <https://docs.fd.io/vpp/18.07/clicmd.html>`_ .
+
+Show Bridge-Domain
+===================
+
+`Show Bridge-Domain <../interface/hardware.html#show-bridge-domain>`_
+
+Show Interface
+================
+
+`Show Interface <../interface/basic.html#show-interface>`_
+
+Show IP Arp
+============
+
+Summary/Usage
+---------------
+
+show ip arp
+
+Description
+------------
+
+Display all the IPv4 ARP entries.
+
+Example Usage
+--------------
+Example of how to display the IPv4 ARP table:
+
+.. code-block:: console
+
+   vpp# **show ip arp**
+       Time      FIB        IP4       Flags      Ethernet              Interface
+       346.3028   0       6.1.1.3            de:ad:be:ef:ba:be   GigabitEthernet2/0/0
+      3077.4271   0       6.1.1.4       S    de:ad:be:ef:ff:ff   GigabitEthernet2/0/0
+      2998.6409   1       6.2.2.3            de:ad:be:ef:00:01   GigabitEthernet2/0/0
+    Proxy arps enabled for:
+    Fib_index 0   6.0.0.1 - 6.0.0.11
+
+
+Declaration and Implementation
+-------------------------------
+
+**Declaration:** show_ip4_arp_command (src/vnet/ethernet/arp.c line 1465)
+
+**Implementation:** show_ip4_arp
+
+Show IP Fib
+=============
+
+Summary/Usage
+---------------
+
+show ip fib [summary] [table <*table-id*>] [index <*fib-id*>] [<*ip4-addr*>[/<*mask*>]] [mtrie] [detail]
+
+Description
+------------
+
+This command displays the IPv4 FIB Tables (VRF Tables) and the route entries for each table.
+
+.. note::
+	This command will run for a long time when the FIB tables are comprised of millions of entries. For those senarios, consider displaying a single table or summary mode.
+
+Example Usage
+--------------
+Example of how to display all the IPv4 FIB tables:
+
+.. code-block:: console
+
+    vpp# **show ip fib**
+
+    ipv4-VRF:0, fib_index 0, flow hash: src dst sport dport proto
+    0.0.0.0/0
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:0 buckets:1 uRPF:0 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    0.0.0.0/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:1 buckets:1 uRPF:1 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    6.0.1.2/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:30 buckets:1 uRPF:29 to:[0:0]]
+      [0] [@3]: arp-ipv4: via 6.0.0.1 af_packet0
+    7.0.0.1/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:31 buckets:4 uRPF:30 to:[0:0]]
+      [0] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
+      [1] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
+      [2] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
+      [3] [@3]: arp-ipv4: via 6.0.0.1 af_packet0
+    224.0.0.0/8
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:3 buckets:1 uRPF:3 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    240.0.0.0/8
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:2 buckets:1 uRPF:2 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    255.255.255.255/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:4 buckets:1 uRPF:4 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    ipv4-VRF:7, fib_index 1, flow hash: src dst sport dport proto
+    0.0.0.0/0
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:12 buckets:1 uRPF:11 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    0.0.0.0/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:13 buckets:1 uRPF:12 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    172.16.1.0/24
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:17 buckets:1 uRPF:16 to:[0:0]]
+      [0] [@4]: ipv4-glean: af_packet0
+    172.16.1.1/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:18 buckets:1 uRPF:17 to:[1:84]]
+      [0] [@2]: dpo-receive: 172.16.1.1 on af_packet0
+    172.16.1.2/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:21 buckets:1 uRPF:20 to:[0:0]]
+      [0] [@5]: ipv4 via 172.16.1.2 af_packet0: IP4: 02:fe:9e:70:7a:2b -> 26:a5:f6:9c:3a:36
+    172.16.2.0/24
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:19 buckets:1 uRPF:18 to:[0:0]]
+      [0] [@4]: ipv4-glean: af_packet1
+    172.16.2.1/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:20 buckets:1 uRPF:19 to:[0:0]]
+      [0] [@2]: dpo-receive: 172.16.2.1 on af_packet1
+    224.0.0.0/8
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:15 buckets:1 uRPF:14 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    240.0.0.0/8
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:14 buckets:1 uRPF:13 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    255.255.255.255/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:16 buckets:1 uRPF:15 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+
+Example of how to display a single IPv4 FIB table:
+
+.. code-block:: console
+
+    vpp# **show ip fib table 7**
+
+    ipv4-VRF:7, fib_index 1, flow hash: src dst sport dport proto
+    0.0.0.0/0
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:12 buckets:1 uRPF:11 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    0.0.0.0/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:13 buckets:1 uRPF:12 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    172.16.1.0/24
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:17 buckets:1 uRPF:16 to:[0:0]]
+      [0] [@4]: ipv4-glean: af_packet0
+    172.16.1.1/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:18 buckets:1 uRPF:17 to:[1:84]]
+      [0] [@2]: dpo-receive: 172.16.1.1 on af_packet0
+    172.16.1.2/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:21 buckets:1 uRPF:20 to:[0:0]]
+      [0] [@5]: ipv4 via 172.16.1.2 af_packet0: IP4: 02:fe:9e:70:7a:2b -*> 26:a5:f6:9c:3a:36
+    172.16.2.0/24
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:19 buckets:1 uRPF:18 to:[0:0]]
+      [0] [@4]: ipv4-glean: af_packet1
+    172.16.2.1/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:20 buckets:1 uRPF:19 to:[0:0]]
+      [0] [@2]: dpo-receive: 172.16.2.1 on af_packet1
+    224.0.0.0/8
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:15 buckets:1 uRPF:14 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    240.0.0.0/8
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:14 buckets:1 uRPF:13 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+    255.255.255.255/32
+      unicast-ip4-chain
+      [@0]: dpo-load-balance: [index:16 buckets:1 uRPF:15 to:[0:0]]
+      [0] [@0]: dpo-drop ip6
+
+Example of how to display a summary of all IPv4 FIB tables:
+
+.. code-block:: console
+
+    vpp# **show ip fib summary**
+
+    ipv4-VRF:0, fib_index 0, flow hash: src dst sport dport proto
+        Prefix length         Count
+                       0               1
+                       8               2
+                      32               4
+    ipv4-VRF:7, fib_index 1, flow hash: src dst sport dport proto
+        Prefix length         Count
+                       0               1
+                       8               2
+                      24               2
+                      32               4
+
+Declaration and Implementation
+-------------------------------
+
+**Declaration:** ip4_show_fib_command (src/vnet/fib/ip4_fib.c line 873)
+
+**Implementation:** ip4_show_fib
+
+Show L2fib
+============
+
+Summary/Usage
+------------------
+
+show l2fib [all] | [bd_id <*nn*> | bd_index <*nn*>] [learn | add] | [raw]
+
+Description
+------------
+
+This command displays the MAC Address entries of the L2 FIB table. Output can be filtered to just get the number of MAC Addresses or display each MAC Address for all bridge domains or just a single bridge domain.
+
+Example Usage
+--------------
+Example of how to display the number of MAC Address entries in the L2 FIB table:
+
+
+.. code-block:: console
+
+    vpp# **show l2fib**
+
+    3 l2fib entries
+
+    Example of how to display all the MAC Address entries in the L2 FIB table:
+
+    vpp# **show l2fib all**
+
+        Mac Address     BD Idx           Interface           Index  static  filter  bvi  refresh  timestamp
+     52:54:00:53:18:33    1      GigabitEthernet0/8/0.200      3       0       0     0      0         0
+     52:54:00:53:18:55    1      GigabitEthernet0/8/0.200      3       1       0     0      0         0
+     52:54:00:53:18:77    1                 N/A                -1      1       1     0      0         0
+    3 l2fib entries
+
+Declaration and Implementation
+-------------------------------
+
+**Declaration:** show_l2fib_cli (src/vnet/l2/l2_fib.c line 311)
+
+**Implementation:** show_l2fib
+
+Show Trace
+===========
+
+Summary/Usage
+--------------
+
+show trace buffer [max COUNT]
+
+Declaration and Implementation
+------------------------------
+
+**Declaration:** show_trace_cli (src/vlib/trace.c line 347)
+
+**Implementation:** cli_show_trace_buffer
+
+Show Vhost-User
+================
+
+`Show Vhost-User <../vhost/vhostuser.html#show-vhost-user>`_
+