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Windows XP SP3 and DNS Issues

This may be useful to a lot of system admins as a definitive answer to a very strange DNS Issue in Windows XP. The situation, you can do “Nslookup google.com”, and you get the following:

Name: google.com

Addresseses: 74.125.45.100 ….

However, when you do a ping google.com, it times out. Also, whenever you go onto the internet, you get either a timeout / error 404, or a similar error message.

Finally, whenever you type in the ip address of a website, e.g. http://74.125.45.100 – google, it loads. So we know the network works, and the internet works as we can nslookup and get an internet browser onto a webpage.

This can be very confusing so i thought i’d post why this happens and what makes it happen.

There is obviously a DNS problem, as you cannot resolve any Domain Name to an IP address; so why does NSLOOKUP work? The answer, is simply NETBIOS. Microsoft, being the brilliant confusers they are, decide that one resolution wasnt good enough so added NETBIOS. NSLOOKUP resolves IP address by using a NETBIOS packet / protocol, which is why you can resolve google.com etc in NSLOOKUP but not in PING, HTTP etc.

This seems to be an issue with Windows XP SP3 – once uninstalled the error should be resolved.

Sam.

Tags: DNS, Problems, SP3, Windows

Windows 7 Blog Announced

A blog has finally appeared from the guys behind the development of Microsofts hush-hush OS, Windows 7. The blog can be found here http://blogs.msdn.com/e7/archive/2008/08/14/welcome.aspx

There isnt much interesting on it at the moment – mainly introductions, what we intend to achieve, etc. However after the couple of Microsoft forums which are coming up in the future, its safe to assume that more details will follow. One such rumour is that Microsoft are set to take advantage of Jeff Han’s multi-touch research by building the technology into their Operating System (Jeff Hans research page is here http://www.cs.nyu.edu/~jhan/ftirtouch/) 

There is a video of the technology here http://link.brightcove.com/services/link/bcpid713271701/bclid713073346/bctid709364416 While Microsoft may claim this as new, this technology has been around now for nearly 3 years – i remember Matt sending me a link to their video at the beginning of 2006. It is fascinating yes, but at the same time it all depends on A) Everyone going out and buying a touch screen (not going to happen!) and B) People coding API’s for their touch screens and C) Windows not being over-zealous like they were with Vista and its driver certification -  otherwise they’ll have the OS, the Apps, but all the hardware makers of touch-screen interfaces (Zalman etc) wont have their drivers “digitally signed” or whatever nonsensical term Microsoft are using nowadays.

Good luck, but much like SSD i think we’re a long way off yet.

Tags: jeff han, multi-touch, Windows, windows 7

Lets Get Started: Para-Virtualization

First off, i’d like to just get the site kicked off with a brief +/- i wrote a few weeks ago on Para-virtualization.

http://img440.imageshack.us/img440/8415/800pxviridianarchitecturl4.png

+ Paravirtualization (PV) provides major security benefits, as the host server generally cannot access the virtual machines inside (if compromised) unlike Full Virtualization (FV). Also, virtual machines are totally black-boxed, and cannot see other VM’s on the same server.

+ PV provides an infrastructure with a lot more redundancy, backup and fail-over options than FV; using proprietary technologies such as “VMotion” (VMWare) which allow a virtual machine to be ran across 2 separate physical hosts in 2 separate locations.

- PV is expensive to run; as you will need hardware that is officially supported to run the hardware on (generally), compared to FV, such as VMWare Server, which you can install on any hardware running a supported Operating system such as Ubuntu, Win. XP, etc.

http://blogs.vmware.com/vmtn/images/2007/11/15/multimode.png

- Most common variant of Virtualization used in the Enterprise today.
- Examples include VMWare ESX/Vi3, XenSource aka Citrix.
- Uses a “Hypervisor” or Virtual Machine Monitor, to allow multiple OS to run on a host computer simultaneously. VMWare uses vmkernel as its Hypervisor.

Tomorrow -  Hypervisor types.

Tags: Add new tag, ESX, Hyper V, Hypervisor, Microsoft, Para, Para-Virtualization, Ubuntu, Virtualization, VMWare, Windows, Windows XP