Added support info.

docs/source/includes/_links.rst

@@ -9,3 +9,6 @@
 .. _mibs.pysnmp.com: https://github.com/lextudio/mibs.snmplabs.com/tree/master/asn1
 .. _pyenv: https://github.com/pyenv/pyenv
 .. _pyenv-win: https://github.com/pyenv-win/pyenv-win
+.. _Wireshark: https://www.wireshark.org/
+.. _tcpdump: https://www.tcpdump.org/
+.. _Net-SNMP: http://www.net-snmp.org/

docs/source/troubleshooting.rst

@@ -6,6 +6,12 @@ Troubleshooting
 .. toctree::
    :maxdepth: 2
 
+Don't panic when your PySNMP application does not work as expected. This
+page provides some tips and tricks to troubleshoot your PySNMP application.
+
+PySNMP Built-in Debugging
+-------------------------
+
 If you find your PySNMP application behaving unexpectedly, try to enable
 a /more or less verbose/ built-in PySNMP debugging by adding the
 following snippet of code at the beginning of your application:
@@ -35,6 +41,28 @@ specific flags are:
 You might refer to PySNMP source code to see in which components these
 flags are used.
 
+Common Utilities
+----------------
+
+While built-in debugging is a good start, you might want to use some other
+tools and utilities to troubleshoot your PySNMP application at packet level
+so as to gain more insights. Then you might want to use some tools below,
+
+- `Wireshark`_ is a great tool to see what's going on the wire.
+- `tcpdump`_ is a command-line tool to capture network traffic.
+- `Net-SNMP`_ command-line tools are great to see how your SNMP agent
+  responds to requests.
+
+Commercial Support
+------------------
+
+If you are still stuck, you might want to consider hiring a professional to
+help you out.
+
+`LeXtudio Inc.`_ does not only support PySNMP ecosystem by maintaining the
+GitHub repositories but also offers commercial support such as consulting
+services. You can easily open a support ticket via its homepage.
+
 References
 ----------