Debugging-and-Troubleshooting.md

-# Debugging and Troubleshooting
-
-### Monitoring Traffic
+## Monitoring Traffic
 
 Sniffing traffic can be a very powerful tool when debugging your P4 program. Basic things like verifying
 if traffic crosses certain path, or if header fields look like expected can be easily achieved by just
 observing traffic. For that, there is a wide range of tools that can be used:
 
-#### Pcap Files:
+### Pcap Files:
 
 The `simple_switch` provides an option to save all the traffic that crosses its interfaces in a pcap file. To
 enable pcap logging when starting your switch, use the `--pcap=<output_dir>` command line option. For Example:
@@ -21,7 +19,7 @@ Pcap logging will create several files using the following naming: `<sw_name>-<i
 
 If you enable pcap in the `p4app.json` configuration file, switches will be started with the `--pcap` option and use as output dir `./pcap`.
 
-#### Wireshark/Tshark:
+### Wireshark/Tshark:
 
 Another option is to observe the traffic as it flows. For that you can use tools like `tshark` and its GUI version `wireshark`. Wireshark
 is already installed in the VM, you can find its executable in the desktop.
@@ -32,7 +30,7 @@ To capture traffic with tshark run:
 sudo tshark -i <interface_name>
 ```
 
-#### Tcpdump:
+### Tcpdump:
 
 Similarly, and if you prefer, you can use `tcpdump` (also already installed in the VM).
 
@@ -42,11 +40,11 @@ To capture traffic with tcpdump run (shows link-layer information and does not r
 sudo tcpdump -l -enn -i <interface_name>
 ```
 
-### Logging
+## Logging
 
 To enable logging, make sure that you enabled `--with-nanomsg` flag to `configure` before compiling `bmv2`.
 
-#### Console logging
+### Console logging
 
 To enable console logging when starting your switch, use the `--log-console` command line option. For example:
 
@@ -61,17 +59,17 @@ it to a log file:
 sudo simple_switch -i 0@<iface0> -i 1@<iface1> --log-console <path to JSON file> >/path_to_file/sw.log
 ```
 
-#### P4 Utils Integration
+### P4 Utils Integration
 
 If you enable logging in the `p4app.json` configuration file, switches will automatically write all the console logging
 into a file in the `./log` directory and with `<sw_name>.log`.
 
-#### CLI logging
+### CLI logging
 
 If logging is enabled, and you use the `simple_switch_CLI` when starting the topology (with `p4utils`) the output
 of the `cli` will be also logged in the log folder under the name `<sw_name>_cli_output.log`
 
-#### Event logging
+### Event logging
 
 To enable event logging when starting your switch, use the *--nanolog* command
 line option. For example, to use the ipc address *ipc:///tmp/bm-log.ipc*:
@@ -94,7 +92,7 @@ to check the `print` messages displayed by `p4run`. Try to find a line that look
 s1 -> Thrift port: 9090
 ```
 
-### Debugger
+## Debugger
 
 To enable the debugger, make sure that you passed the `--enable-debugger` flag
 to `configure`. You will also need to use the `--debugger` command line flag
@@ -108,7 +106,7 @@ attach the debugger to the switch:
 You can find a P4 debugger user guide in the bmv2
  [docs](https://github.com/p4lang/behavioral-model/blob/master/docs/p4dbg_user_guide.md).
 
-### Attaching Information to a Packet
+## Attaching Information to a Packet
 
 Some times you do not want to use the logging system or debugger, or basically they are disabled. Yet, you could still
 get some insights on what the code does by just modifying a header field depending on which part of the code
@@ -116,14 +114,14 @@ gets executed and check that value when the packet leaves the switch. Of course
 and use several fields, read the value of a register and save it in the header, and so on.
 
 
-### Using P4 tables to inspect headers/metadata values
+## Using P4 tables to inspect headers/metadata values
 
 We already have an [example](../examples/debugging_table/README.md) covering this. Basically the idea is to use
 P4 tables and do an `exact` match to all the fields you want to track. Every time the table is executed, if the bmv2
 debugging is enabled, the switch will write the values of each field that was used to match the table entry in the switch
 log file. See the example for more information.
 
-### If the above did not solve your problem:
+## If the above did not solve your problem:
 
 P4, and all the tools around are quite new. Several times things just do not work
 because there is a bug in the compiler or in the software switch implementation.