Archive for the ‘network’ Category

VirtualBox: accessing the guest from the host

September 23, 2013 Leave a comment

In a VirtualBox guest machine I wanted to set up a web server for testing purposes. How to access the guest’s web server from the host?

In the guest’s network settings, normally you already have a NAT network adapter. This way the guest can access the Internet.

But how to establish a network communication between the host and the guest? In the guest’s network settings, select the tab “Adapter 2″. At home “Bridged Adapter” worked for me.

However, at my workplace “Bridged Adapter” didn’t work. After some research I wanted to try “Host-only Adapter”, but I ran into a difficulty. I couldn’t add a host-only adapter, I got the following error message: “no host-only network adapter selected”. And the GUI didn’t offer anything in the dropdown list :(


Fortunately I found the solution here. The image above was also borrowed from

For future references, I quote the steps here:

Probably, the virtual host-only network wasn’t set up yet. Here’s is how you can fix this:

  1. From the main menu, select File > Preferences (Ctrl+G) – NOT the settings of a single vm
  2. Select Network in the list on the left
  3. You should see an empty white box with “Host-only Networks” at the top. On the right, there are three buttons to manage them. Click the topmost one (with a green plus symbol). A new Host-only network will be created and added to the list.

Normally, the settings of the new network will be ok, but for completeness, I give the default values here. You can access the settings for the host-only network through the screwdriver button on the right.

  • Adapter:
    • IPv4 address:
    • IPv4 Network Mask:
  • DHCP server:
    • Enable server: checked
    • Server Address:
    • Server Mask:
    • Lower Address Bound:
    • Upper Address Bound:

You can change these settings to your liking, as long as they’re consistent.

Thanks to Bert Van Vreckem for this great answer.

Guest’s IP address
Executing “ifconfig” in the guest, you’ll get its IP address. Mine is under “eth1″, next to “inet addr:”. Try to ping the guest from the host and vice versa. They should work :)

Categories: network Tags: , , ,

What is my IP address?

October 20, 2011 4 comments

You want to figure out your IP address.

New way
Visit Google and type in “what is my ip“, or just simply “my ip“. Direct link:

Old way

Sexy way

This tip is from here (in Hungarian).

Categories: google, network Tags:

Who is hosting a given website?

March 9, 2011 1 comment

To find out who is hosting a given website, visit


Related work

You can also install the Flagfox Firefox add-on. Then, with a simple click you can get lots of information about the current page you are visiting.

Categories: firefox, network Tags: , ,

Is a given website down or not?

March 9, 2011 1 comment


Your favorite website doesn’t want to load. Is the given website down? Or is there a temporary problem with your network provider?


Try the website Normally they check your site from three random stations around the world. If 2 or more stations find an error or do not get response within 4 seconds, the site is considered to be “down”.

Tip: on the main page of Down Or Not, there is a cloud with the most popular searches. Check out the cloud to find out what’s hot today…

Other methods
Some alternative methods:

  • ping HOST
  • traceroute HOST

Where HOST is the site you want to check. However, these two methods are not too reliable for checking if a website is up. I just checked a site that was definitely up, but both ping and traceroute failed to reach it.

Categories: network Tags: , , ,

IPv6 Connectivity Test

January 25, 2011 Leave a comment


You want to test your connection whether it’s IPv6 (preferred) or IPv4 (old and crusty).


Visit these test sites:

They are also good to figure out your IP address.

Read more

See Betelt az internet; Világkáosz és zűrzavar; Június 8. lesz az IPv6 napja (in Hungarian).


Categories: network Tags: , , , ,

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