How To Capture Packets With VLAN Tag

Required: 2 PCs/Laptops, a switch (VLAN supported) and wireshark
Diagram:

You may find simpler way to do it in somewhere else’s blog (e.g. packetLife) but my idea comes the characteristic of broadcast. That is the broadcast will send out to everywhere in the broadcast domain including ports which are in TRUNK mode on the same switch. Configuration is simple as suggested in the diagram. And I just send a ping to 10.10.10.255 from PC1 which is in the same network or VLAN and the wireshark running on the PC2 which is connected to the trunk mode has captured that:



You can see that the 802.1Q tag has got captured. I am not sure whether you have noticed that the first three bits in the tag has been set to be 101 which is 5 in decimal. That is to illustrate that the QoS classification at level 2 can be done via setting the CoS bits which are carried by the 802.1Q tag.

Use Windows System Image Manager to Create Unattended files for Windows 7 installation

I became quite frustrated when I was in a stage where I need a unattended.xml to facilitate Windows 7 deployment in SCCM 2007 environment as there is little information about how to generate it. While Microsoft does have several sample unatteded files but I think what I want is to customize the file as I wish rather than copy and paste from Microsoft samples.


So I open my eyes wide and finally found something that is really capable of doing what I want to. It is still from Microsoft though. Well the toolkit name is Windows System Image Manager which is part of the Microsoft AIK.

Once you open that up, you are to load an image (just use install.wim in Windows 7 DVD) or a catalog file in the installation source.

After loading up an image or clg file at the left pane, then what you see is a total list of features / settings that you can customize and put into unattended file. Taken the screenshot as an example, the International-Core is related to regional settings in the Windows. So if you want to customize it, just right-click on that item and Add to of the passes in the middle. Each pass is just like a stage in the unattended installation and you don't have to know too much about pass to finish editing your own unattended file!

After you place the feature /setting component in the answer file passes, you need to give proper values accordingly and repeat the steps as needed. My below screenshot showed that I only have one customized setting which is regional setting that was set to be en-au. 

Right click on Untitled in the middle pane, you'll be able to save the work and start using the unattended files.

Difference between ip access-list and access-list

There are two ways to configure access list on cisco devices:

a. Using access-list command and b. Using ip access-list. The difference lies between them will make you think twice before you choose one of them.

Here is is an simple example to configure a standard access list using method a.:

Look at what you got after you delete one of the items in the access list created by method a.:

The standard access list  is gone even you only delete one of multiple access list entries!

Now look at the example below to see how to configure a standard access list using method b.:

Now look at what you got after you delete one of the items in the access list created by method b.:

This is great and provides more flexibility in designing and managing access lists. 

Besides, using ip access-list also gives you the option to design named access list.

Where is Configuration Manager Client Icon in Windows XP 64 Bit

I've have recently finished SCCM OSD task sequence design to deploy Windows XP 64 Bit. But I've almost fooled myself to believe my task sequence failed in the end just because I can't find the icon in Control Panel.

In fact the ConfigMgr client icons are "grouped" in the Control Panel where you would find "View x86 Control Panel Icons" link at the left pane. Click on it, you'll get'em.

In 64Bit OS, the CCM folder is not under C:\Windows\System32 any more but it sits in C:\Windows\SysWOW64\

How To Bypass RemoteApp Launch Security Warning "unknown publisher"

Never thought my first post here will be technical related, but I've gotta face the truth that starting with technical hints and tips would be more appealing to those I.T dudes. Anyway, I write the blog to share the experience that I have suffered from the annoying security prompt when user launched RemoteApp connection and it took me a while to successfully resolve this.

For those who suffering from the same issue would be familiar with this:

Actually we can get rid of this by ticking the option to avoid seeing this again. But in a larger organization, you could imagine that would not be an easy task to ask everybody to do it and it is not an elegant way to do it.  To avoid post-deployment nuisances, you can either sign the RDP file with a legitimate certification or get around this by just modifing registry without risks.


The location in registry you need to hack on is:
[HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client\LocalDevices]
"ServerFQDNname"=dword:0000006f


So in registry, after modification it looks like:

The only cons is the fact that you have to make the change for each RemoteApp server.