Archive for October, 2010

Installing Webmin on CentOS

// October 26th, 2010 // Comments // Technology

I recently got a MediaTemple VE Server, one of the best unmanaged VPS servers available today. Its built to be a highly efficient and performant utility VPS, with high-end hardware, top-tier connectivity and superior virtualization technology.

The only one head-ache with this server is that you have to manage everthing from top to bottom. Linux Server Management is obviously not a easy task for newbies. However there are various ready tools to reduce this headache, however you will have to setup them on your own initially.

My choice of control panel was Webmin. Webmin is one of the best open source control panel. Here goes the official description:

Webmin is a web-based interface for system administration for Unix. Using any modern web browser, you can setup user accounts, Apache, DNS, file sharing and much more. Webmin removes the need to manually edit Unix configuration files like /etc/passwd, and lets you manage a system from the console or remotely.

So now lets install webmin step by step:

Step 0 : Install dependencies

For CentOS 5.1 (or lower) we need to install few dependecies. Just connect to your server through SSH and use the following command:

yum -y install perl-Net-SSLeay

Note: This step is not required in case you are using CentOS 5.2 or above, since they are already present.

Step 2 : Install Webmin

a. Change the directory using the following command

$ cd /usr/src

b. Download webmin package from http://www.webmin.com/download.html

$ wget http://prdownloads.sourceforge.net/webadmin/webmin-1.520-1.noarch.rpm

Note: You can replace the download link with the latest version of the package.

c. Install RPM

$ rpm -i webmin-1.520-1.noarch.rpm

Step 2: Open Webmin

To open webmin just open the browser and type https://your-ip-address:10000 like the example below:

https://420.420.420.420:10000
Once you open the link in the url you see a login window like below:
Webmin Login Window

You can login with your root username and password.

Step 3: Start using webmin !

Outputs of my Installation process is as below:

[[email protected] ~]# cd /usr/src
[[email protected] src]# wget http://prdownloads.sourceforge.net/webadmin/webmin-1.520-1.noarch.rpm
--2010-10-23 00:52:20--  http://prdownloads.sourceforge.net/webadmin/webmin-1.520-1.noarch.rpm
Resolving prdownloads.sourceforge.net... 216.34.181.59
Connecting to prdownloads.sourceforge.net|216.34.181.59|:80... connected.
HTTP request sent, awaiting response... 301 Moved Permanently
Location: http://downloads.sourceforge.net/project/webadmin/webmin/1.520/webmin-1.520-1.noarch.rpm [following]
--2010-10-23 00:52:21--  http://downloads.sourceforge.net/project/webadmin/webmin/1.520/webmin-1.520-1.noarch.rpm
Resolving downloads.sourceforge.net... 216.34.181.59
Reusing existing connection to prdownloads.sourceforge.net:80.
HTTP request sent, awaiting response... 302 Found
Location: http://iweb.dl.sourceforge.net/project/webadmin/webmin/1.520/webmin-1.520-1.noarch.rpm [following]
--2010-10-23 00:52:21--  http://iweb.dl.sourceforge.net/project/webadmin/webmin/1.520/webmin-1.520-1.noarch.rpm
Resolving iweb.dl.sourceforge.net... 70.38.0.134
Connecting to iweb.dl.sourceforge.net|70.38.0.134|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 16094665 (15M) [application/x-redhat-package-manager]
Saving to: `webmin-1.520-1.noarch.rpm'

100%[======================================>] 16,094,665  3.66M/s   in 4.3s    

2010-10-23 00:52:25 (3.60 MB/s) - `webmin-1.520-1.noarch.rpm' saved [16094665/16094665]

[[email protected] src]# rpm -i webmin-1.520-1.noarch.rpm
warning: webmin-1.520-1.noarch.rpm: Header V3 DSA signature: NOKEY, key ID 11f63c51
Operating system is CentOS Linux
Webmin install complete. You can now login to http://ve.p26dhbmy.vesrv.com:10000/
as root with your root password.

Additionaly you can use virtualmin and usermin along with webmin.

I shall explain you regarding installation of virtuamin and usermin in the coming days.Stay tuned 🙂

RESOLVE: REMOTE HOST IDENTIFICATION HAS CHANGED!

// October 23rd, 2010 // Comments // Old

Recently I re-installed my MediaTemple Ve Server. I successfully installed CentOS 5 on MediaTemple Ve server. After installation I tried to connect to server through SSH. Unfortunately got a message saying WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!  It looked something like below:

$ ssh [email protected]

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
1e:e3:c4:0a:6a:78:e6:17:cc:f2:ba:ca:c7:39:4b:aa.
Please contact your system administrator.
Add correct host key in /Users/sandeephegde/.ssh/known_hosts to get rid of this message.
Offending key in /Users/sandeephegde/.ssh/known_hosts:1
RSA host key for 420.420.420.420 has changed and you have requested strict checking.
Host key verification failed.

Looked around to resolve the issue. Got to know that the issue was due to the old RSA key stored in the system. The solution to resolve the issue was to add the correct key. Easiest way is to remove all the old RSA keys from your computer. To do this simply go to your terminal and type as below:

$ open .ssh

This will result in opeing a windows as in screenshot:

RSA Host Keys

All that you have to do is delete the file “know_hosts” i.e simply move it to trash. Thats all you have got rid of REMOTE HOST IDENTIFICATION HAS CHANGED!

Now you can connect to you server through SSH normally. If you are still facing any difiulities leave a comment below.