VMware ESXi: Setting up NAT with a linux virtual machine

Hi,

other than the Workstation, VMware ESXi does not has the functionality to “NATting” virtual machines network traffic into a public network.

My approach to implement NAT is a virtual machine with a slimmed-down (Debian) Linux.

These virtual machine has two network interfaces. The first interface is connected to a vSwitch called “Public LAN” with access to the public LAN, the second interface is connected to a vSwitch which has no physical adapter attached to and is called “NAT Network”. On the NAT interface a DHCP server is assigning IP Addresses.
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Windows: No installation of Windows Updates at a policy defined scheduled date and time

Hi,

since Windows 8 respectively Server 2012 the policy to install Updates at a specific date and time has no affect.

Microsoft changed the behaviour for installing updates. The schedule for a installation and restart of updates is just defined by the deadline for Updates on the WSUS Server.
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Security: Check a webserver for heartbleed vulnerability with nmap

Hi,

here is a short tutorial to check a webserver with nmap.

Update to the latest version of nmap. Otherwise nmap would not work (Error message:/usr/bin/../share/nmap/scripts/ssl-heartbleed.nse:40: This script requires the tls.lua library….). For example debian wheezy. Add the backport repository “deb http://ftp.uni-erlangen.de/debian/ wheezy-backports main” to /etc/apt/sources.list.

Refresh sources

root@debdev:/# apt-get update

Install the latest nmap version
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Powershell: A text based menu

Hi,

a long time ago I wrote a Menu function for quickly choose predefined options in a script. An example

Source the menu.ps1 in your script and call  fShowMenu. This will show the menu. The function needs 2 parameters:
Parameter 1: The menu title as string
Parameter 2: A hashtable with the Menuentries. The key of an Menuitem is returned by the function the corresponding value is shown at the menu.

# Source the file
. .\menu.ps1
# Call Menu funtion
fShowMenu "Choose your favorite Band" @{"sl"="Slayer";"me"="Metallica";"ex"="Exodus";"an"="Anthrax"}
A text based Powershell Menu
A text based Powershell Menu

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OpenVPN: Change the default TCP/UDP Ports

Hi,

sometimes it make sense to change the default ports of an OpenVPN installation, because these are those which are in case of an vulnerability scan attacked first or some company firewall rules makes it necessary.

With the

port 1194

directive in your config file the source and destination port for connections is always 1194.

For outgoing connections there are two ways to alter the source port:
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