Troubleshooting

How to Find Public IP Address from CLI

Often, an IP address is hidden behind a proxy or NAT. Here is how you can tell the public IP:

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Blue Coat Packet Capture

The Blue Coat Proxy / Filter device transfers packets like any other network device. A simple troubleshooting technique is to see if the packets are flowing through the device as expected. Here are the commands to do a Blue Coat Packet Capture:

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tcpdump filters

A common step in troubleshooting is finding out what not to troubleshoot. With a packet capture you can confirm things such as routing, firewall rules, and remote services.

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Network Troubleshooting With Telnet

Using Telnet to Test Open Ports The Setup on Digitalcrunch.com: 5555 is blocked via a firewall 80 is open and running http service 22 is open and running ssh How to Manually Use Telnet Typing anything and then hitting enter is like sending protocol information to the remote service. If you know the protocol and [...]

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Disable Windows Firewall

The windows firewall is actually pretty good at blocking inbound traffic, and even outbound traffic if configured properly. The interface is horrible though! You can get to the control panel by typing wf.msc, but you can also disable windows firewall from the cli. Here are some other useful commands:

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