There is a nice little trick or tool in Cisco that we can use when we troubleshoot network problems. It is very simple and useful:)
Sometimes I need to configure a test Windows virtual machine and use it for only for a week or two. Well if you are using a Microsoft Windows Server 2008 R2 OS like me and you have only 3 days till activation then continue in reading this post:)
After the connection between two switches could not be established I went to see the log of the uplink switch and the first thing I have noticed was this:
%LINK-3-UPDOWN: Interface FastEthernet0/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
%SPANTREE-7-RECV_1Q_NON_TRUNK: Received 802.1Q BPDU on non trunk FastEthernet0/1 VLAN300.
%SPANTREE-7-BLOCK_PORT_TYPE: Blocking FastEthernet0/1 on VLAN0300. Inconsistent port type.
After moving your DHCP server and it doesn’t receive client requests but everything is “OK” with the server, then that could cause a problem in your corporate environment:)
I wanted to use in my test environment an NTP server on Microsoft Windows Server 2008 R2 that would function as a syncing point for my Cisco routers and switches. The starting issue is that Cisco devices will not sync with Windows integrated NTP server and the reason is that Windows use SNTP as network time protocol.
Continue reading “Microsoft Windows Server 2008 as NTP server for Cisco devices”
Here are a few notes how to successfully simulate an IPS 6 instance in GNS3. Version 7 is a little tricky to simulate so I suggest you get the IPS Manager Express and practice everything in the demo that is available when you install it.
Continue reading “GNS3 IPS simulation”
Although this procedure is written in the official Cisco documentation, I will give you my understanding (example) of it.
Command syntax is the only part where I have encountered some problems (errors).
Continue reading “Cisco LMS 3.2 Restore Procedure and Misc”
Here I want to share a script that my friend selflessly shared with me:)
In the installation process of Windows Server 2012 you are given a choice would you like to install the Server Core Installation or the Server with the GUI.
A great feature is that we are given a possibility to revert back and forth between a GUI and the non GUI…
We have to use Powershell for this and I recommend that you get pretty comfortable with it – I am also trying:)
We will start with the GUI edition and convert it to a full Core version without the GUI.
In Powershell type:
Wait a moment…
After the completion a restart will be needed.
After restart and a successful login only a command line prompt window will show. Type “Powershell” to start Powershell.
To revert to full GUI edition just type “Add-WindowsFeature Server-Gui-Shell, Server-Gui-Mgmt-Infra” and restart server!
This is also all possible with the famous DISM (Deployment Image Servicing and Management) tool. This is the command:
“Dism /online /enable-feature /featurename:ServerCore-FullServer /featurename:Server-Gui-Shell /featurename:Server-Gui-Mgmt”
If you don’t like the core or the GUI version maybe you could meet with the “Minimal Server Interface” concept in the middle. In short, the only thing that you remove is the “Server-Gui-Shell”.
Line from technet: “This is similar to a Server with a GUI installation, but Internet Explorer 10, Windows Explorer, the desktop, and the Start screen are not installed. Microsoft Management Console (MMC), Server Manager, and a subset of Control Panel are still present.”
More details about Minimal Server Interface and the rest of the implementations you can find here –> http://technet.microsoft.com/en-us/library/hh831786.aspx
It has been a few months since my last blog post and reason for that is the lack of time and of course – my laziness:)
Here we will talk about an interesting Mozilla Firefox Add-on and the whole concept around the X-Forwarded-For header.
Continue reading “Mozilla Firefox X-Forwarded-For header Add-on”