GeekLab

Connect two netcats to each other

<span style="color: #c20cb9; font-weight: bold;">mkfifo</span> backpipe

nc localhost <span style="color: #000000;">55545</span> <span style="color: #000000;">0</span><span style="color: #000000; font-weight: bold;">&lt;</span>backpipe <span style="color: #000000; font-weight: bold;">|</span> nc localhost <span style="color: #000000;">55546</span> <span style="color: #000000;">1</span><span style="color: #000000; font-weight: bold;">&gt;</span>backpipe

Telnet with readline and a history:

socat <span style="color: #660033;">-d</span> <span style="color: #660033;">-d</span> READLINE,<span style="color: #007800;">history</span>=<span style="color: #007800;">$HOME</span><span style="color: #000000; font-weight: bold;">/</span>.http_history \

TCP4:www.domain.org:www,crnl

Talk… Read more

CentOS 5's and Fedora 15's base installations are pretty good prepared to use X11 over SSH. You just need to install one more package on the server you're connecting to: xorg-x11-xauth. According to yum info, the purpose of this package is:
xauth is used to edit and display the… Read more

Today I made my first native IPv6 connection. I've been running Teredo/Miredo on my laptop for quite a while now, and I thought it was time to get a real IPv6 connection. I could use IPv6 autoconfiguration, but on a server you need a fixed IP.

Needed software

Install required… Read more

Software that is not reachable, can't be hacked. Easy as that. So if you have an cloud-based anti-spam/anti-virus filter, you can block your smtp server for badguys.

In my situation, I'm using a Windows 2008 SBS server with Exchange 2007.

1. Start wf.msc
2. Go to inbound rules
3. Find MSExchangeTransportWorker and

… Read more

Step 1. Install ntp and synchronize clocks

We'll be using winbind, kerberos and ntlm to authenticate the user. This requires the clocks of the AD server and the proxy server to be synchronized.

[[code]]czoxMDA6XCJycG0gLXFhIG50cCB8fCB5dW0gLXkgaW5zdGFsbCBudHA8YnIgLz4Kc2VkIC1pICZxdW90O3MvXnNlcnZlciAvI3NlcnZ7WyYqJl19ZXIgL2cmcXVvdDsgL2V0Yy9udHAuY29uZjxiciAvPlwiO3tbJiomXX0=[[/code]]

Say you're living in China, and you have no web freedom whatsoever. Or in the Netherlands, and your favorite linux distro download site has been blocked by the corrupt "elite". Then having a tunnel to outside the country could be very useful.

I found two VPN services… Read more

My personal Linux laptop is a real spider in the web. It's got OpenVPN connections to the office, to the datacenter, to serveral family members, etcetera. I love it. But sometimes, there are some tasks that Linux simply can't do, like running a vSphere client.

For those situations, I use… Read more

In this article I'm covering the use of old-style dhcp and tftp, which is useful for company networks that have/need a complete dhcp server running. Personally, for smaller setups, I now prefer dnsmasq to do the job.

Booting from PXE

With most modern onboard and PCI network interface… Read more