Kroko Just another WordPress weblog

January 31, 2008

generate openvpn keys

Filed under: Uncategorized — admin @ 3:02 am

Generate the master Certificate Authority (CA) certificate & key

In this section we will generate a master CA certificate/key, a server certificate/key, and certificates/keys for 3 separate clients.

For PKI management, we will use a set of scripts bundled with OpenVPN.

If you are using Linux, BSD, or a unix-like OS, open a shell and cd to the easy-rsa subdirectory of the OpenVPN distribution. If you installed OpenVPN from an RPM file, the easy-rsa directory can usually be found in /usr/share/doc/packages/openvpn or /usr/share/doc/openvpn-2.0 (it’s best to copy this directory to another location such as /etc/openvpn, before any edits, so that future OpenVPN package upgrades won’t overwrite your modifications). If you installed from a .tar.gz file, the easy-rsa directory will be in the top level directory of the expanded source tree.

If you are using Windows, open up a Command Prompt window and cd to \Program Files\OpenVPN\easy-rsa. Run the following batch file to copy configuration files into place (this will overwrite any preexisting vars.bat and openssl.cnf files):


Now edit the vars file (called vars.bat on Windows) and set the KEY_COUNTRY, KEY_PROVINCE, KEY_CITY, KEY_ORG, and KEY_EMAIL parameters. Don’t leave any of these parameters blank.

Next, initialize the PKI. On Linux/BSD/Unix:

. ./vars

On Windows:


The final command (build-ca) will build the certificate authority (CA) certificate and key by invoking the interactive openssl command:

ai:easy-rsa # ./build-ca
Generating a 1024 bit RSA private key
writing new private key to 'ca.key'
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
Country Name (2 letter code) [KG]:
State or Province Name (full name) [NA]:
Locality Name (eg, city) [BISHKEK]:
Organization Name (eg, company) [OpenVPN-TEST]:
Organizational Unit Name (eg, section) []:
Common Name (eg, your name or your server's hostname) []:OpenVPN-CA
Email Address [me@myhost.mydomain]:

Note that in the above sequence, most queried parameters were defaulted to the values set in the vars or vars.bat files. The only parameter which must be explicitly entered is the Common Name. In the example above, I used “OpenVPN-CA”.

Generate certificate & key for server

Next, we will generate a certificate and private key for the server. On Linux/BSD/Unix:

./build-key-server server

On Windows:

build-key-server server

As in the previous step, most parameters can be defaulted. When the Common Name is queried, enter “server”. Two other queries require positive responses, “Sign the certificate? [y/n]” and “1 out of 1 certificate requests certified, commit? [y/n]”.

Generate certificates & keys for 3 clients

Generating client certificates is very similar to the previous step. On Linux/BSD/Unix:

./build-key client1
./build-key client2
./build-key client3

On Windows:

build-key client1
build-key client2
build-key client3

If you would like to password-protect your client keys, substitute the build-key-pass script.

Remember that for each client, make sure to type the appropriate Common Name when prompted, i.e. “client1”, “client2”, or “client3”. Always use a unique common name for each client.

January 11, 2008

TCPView for Windows v2.52

Filed under: Uncategorized — admin @ 1:48 pm

TCPView for Windows v2.52

By Mark Russinovich

Published: January 4, 2008


TCPView is a Windows program that will show you detailed listings of all TCP and UDP endpoints on your system, including the local and remote addresses and state of TCP connections. On Windows Server 2008, Vista, NT, 2000 and XP TCPView also reports the name of the process that owns the endpoint. TCPView provides a more informative and conveniently presented subset of the Netstat program that ships with Windows. The TCPView download includes Tcpvcon, a command-line version with the same functionality.

TCPView works on Windows Server 2008/Vista/NT/2000/XP and Windows 98/Me. You can use TCPView on Windows 95 if you get the Windows 95 Winsock 2 Update from Microsoft.

TCPView Screenshot

Using TCPView

When you start TCPView it will enumerate all active TCP and UDP endpoints, resolving all IP addresses to their domain name versions. You can use a toolbar button or menu item to toggle the display of resolved names. On Windows XP systems, TCPView shows the name of the process that owns each endpoint.

By default, TCPView updates every second, but you can use the Options|Refresh Rate menu item to change the rate. Endpoints that change state from one update to the next are highlighted in yellow; those that are deleted are shown in red, and new endpoints are shown in green.

You can close established TCP/IP connections (those labeled with a state of ESTABLISHED) by selecting File|Close Connections, or by right-clicking on a connection and choosing Close Connections from the resulting context menu.

You can save TCPView’s output window to a file using the Save menu item.

Tcpvcon Usage

Tcpvcon usage is similar to that of the built-in Windows netstat utility:

Usage: tcpvcon [-a] [-c] [-n] [process name or PID]


Show all endpoints (default is to show established TCP connections).


Print output as CSV.


Don’t resolve addresses.

Microsoft TCPView KB Article

This Microsoft KB article references TCPView:

816944: “Unexpected Error 0x8ffe2740 Occurred” Error Message When You Try to Start a Web Site

Articol preluat de pe:
Download soft:

Powered by WordPress