Recently working on a Debian server, which was not responding to SSH connection. I have checked and found that the SSH service was down and while restarting it it gives following error

sh-3.1# /etc/init.d/ssh restart
PRNG is not seeded
sh-3.1#

I have searched on Google and found that the problem occurs when /dev/random and /dev/urandom are missing from the server.

sh-3.1# ls -al /dev/random
/bin/ls: /dev/random: No such file or directory
sh-3.1# ls -al /dev/urandom
/bin/ls: /dev/urandom: No such file or directory

As it was a VPS I directly logged into it from the host server but in case of Dedicated/Physical Server you will have to use console. Once you logged into the server execute following commands to create /dev/random and /dev/urandom

sh-3.1# mknod /dev/random c 1 9
sh-3.1# mknod /dev/urandom c 1 9

I have found a very nice Tutorial for installation of phpBB3 for any domain.

phpBB is a free flat-forum bulletin board software solution that can be used to stay in touch with a group of people or can power your entire website.

phpBB3 installation include two parts
A) Database configuration.
B) phpBB3 installation.

A) Database configuration.
Login to control panel like Cpanel, Plesk etc. (or any other mysql client) and perform following actions:

1) Create Database
2) Create Database username
3) Database Password
4) Grant Proper Permissions to the users

Read more

Google Chromium OS has been a topic of discussion ever since its launch on July 7 2009. It is a Linux based operating system specially designed for web applications. I tried to search on the internet to get more information about it and came across a beautiful article. I want to share the same article with eITWebguru’s valuable readers, please check following URL:

http://blog.teamgrowth.net/index.php/open-source/build-your-private-chromium-os-chromebook

Proxy server is a computer system or application which is installed on computer system that works as a  acts as an agent or channel for requests from clients looking for resources from other servers. You can check see this post for more information about installation and configuration of Squid Proxy.

Now after installation when you try to check your IP in any site like whatismyip.com it will show that you are using proxy along with the hostname and version of Squid proxy server which is a security concern.

1) Hide Proxy version & server hostname

a) Hide Squid Version

open “/etc/squid/squid.conf” in a editor like vim and search for “httpd_suppress_version_string” and enable it.

Change FROM:

TO:

b) Hide Hostname

Search for “visible_hostname” and change FROM:

TO:

<your desired hostname> will be the name you want to show to world

2) Configure Multiple IP for Squid

Sometime it happens that the Proxy server which you have setup have multiple IP address and you want to configure squid server to use multiple IP addresses (i.e. Systems will show the secondary IP of the server instead of primary). Open squid configuration file; search for “tcp_outgoing_address” and add following

Replace <IP Address> with the IP assigned to your Proxy Server.

Restart Squid Server with command “service squid restart“

Recently we have found that many of Plesk users are complaining about receiving Blank Email to the Plesk Admin address like below

As per Parallels this is the latest bug in Plesk which will be fixed in future releases. They have also provided a work around for the problem; as per them this issue can be temporary fixed by adjusting the permissions of mail handlers hooks. Execute following command from the Shell of your Server.

Scenario

Your Company/Organization/Institute maintains certain data in MSSQL 2000 but now on suggestion of System Analyst or database administrator you want to move the data to MySQL 5.x.

Questions?
1) How to migrate the data?
2) Do we need to recreate the complete database schema?
3) Can we use any third Party Application to convert it and how feasible it will be?
etc.

Solution

Using following steps you can easily move/convert the data from MSSQL to MySql (Only data will be moved).

Downloads Required Tools

1) MySql ODBC connector: MySQL ODBC Connector will help Windows OS to configure MySQL as Database Source Name (DSN). It can be downloaded from http://dev.mysql.com/downloads/connector/odbc/5.1.htm

Install MySql ODBC connector on the Server.

Installation of MySql ODBC connector is pretty easy. You will just have to run setup file and follow the instructions.

Configure MySQL Database Source Name (DSN)

Database Source Name or DSN specifies a data structure that contains the information about a specific data source or database that an Open Database Connectivity (ODBC) driver needs in order to connect to that data source or database. To add new DSN follow the instructions given below

1) Go to “Control Panel -> Administrative Tools -> Data Source” which will open following windows.

Click on “Add…” to add new DSN

2) Select “MySQL ODBC 5.1 Driver” from the list and press “Finish”

3) Once you press Finish “MySQL Connector/ODBC Data Source Configuration” window will open.

Here, provide the information about DSN, database, password etc. I have used Localhost as TCP/IP Server as I have the MySQL server installed locally and migrating it locally. Once the data is filled you can test the DSN connectivity with database. Then Press Ok to configure the DSN.

4) Now ODBC Data Source Administrator will show the Datasource which you have created.

Export/Migrate Data from MSSQL to MySQL using DSN

1) Go to “MSSQL Enterprise Manager >> Databases >> Right Click the database you want to migrate or export >> All Tasks >> Export Data …“

2) You will get “Data Transformation Services Import/Export Wizard” Window. Press next.

3) Choose Source: You have to select the Data Source from where the data will be migrated. As we are going to migrated data from MSSQL to MySQL select “Microsoft OLE DB Provider for SQL Server” and the name of database which you want to migrate.

4) Select Destination: Select “MySQL ODBC 5.1 Driver” from dropdown list which will show the list of DSN in drop-down under “User/System DSN“. Select the DSN you have created and enter the login details.

Press Next to Continue.

5) On “Specify Table Copy or Query” select “Copy table(s) and view(s) from the source database” and press next.

6) Select Source tables(s) and view(s): Select the tables which you want to migrate. I have pressed “Select All” for complete database migration.

Press “Next“

7) Select “Run immediately“; press Next and on next screen press Finish to start Migration.

Now its time to have a cup of coffee and depending upon size of database it will take 20-30 minutes to complete.

_

While setting and configuring NFS share on a server when you try to restart portmap service you get following error

Logs (tail -f /var/log/message) shows that portmap port is conflicting with some other service.

I have searched on internet and found following commands which fixed the issue.

1) Stop portsentry service

2) Restart portmap service

3) Start portsentry service

Try to configure NFS now :)

_

While installation of any package or Starting any service on a RHEL or CentOS based Server you may receive following Error

This Error comes when SELinux setting is enabled on the server. Security-Enhanced Linux (SELinux) is a Linux feature that provides a mechanism for supporting access control security policies through the use of Linux Security Modules (LSM) in the Linux kernel.

By Default SELinux is set to “enforcing” in CentOS on boot, this can be disabled permanently. To disable it edit file “/etc/selinux/config” and change SELINUX

From

TO

But to apply this setting the System or Server need to be rebooted. If you want to disable this feature temporary you can execute following command from the Shell of the System or Server

Recently I have worked on a project where I have to stream a video on Internet which will be then accessed by the Servers on different locations and those servers will then stream the same video to the sub-ordinate systems simultaneously. Using this we can reduce the Load on Main Streaming Server as well as we can save lot of bandwidth as if all the server/systems connect to the Main server directly bandwidth usage of both the server and the client will be very high.

Scenario:
1) Video will be streamed from a Server on Internet.
2) Many other Servers will connect to the Server.
3) These servers will then stream the same video on their network (e.g. on LAN).
4) Users of local system will access the video from secondary servers.

Following image can explain the Scenario in a better way

Step to Stream Video on Primary Server

Following are the steps to stream a video on Primary Server which can be located on remoter location.

1) Login to the Server and install VLC on it.
2) Open VLC Media Player

3) Go to Media >> Streaming

4) Now add the file which you want to stream and Press Stream

5) Source: On Stream Output screen it will show the Source file; press Next to continue

6) Destination: Add HTTP as new destination which will automatically run on port 8080 and you can activate trans-coding as well. Press Next to continue.

7) Others: You will see miscellaneous options which you can select as per your requirement. Press Stream to start Streaming.

8) VLC will start streaming the Video which you have mentioned.

In Next Article I will explain How to setup Secondary Server and clients to watch live streaming

Setting time on a Virtual Machine is always a painful tasks. Different virtualization platform have different techniques of setting time like in Virtuozzo you can change the Timezone of the VM but you can’t set time as it synchronize the time from the host server.

On a Citrix Xen VM also the clocks synchronized to the time running on the host server, and cannot be independently changed. So, when you try to set time (using date -s command) on a Xen VM it will show that the command is executed but it won’t change the time. You can see that in following

To change the time on a VM you need to enable independent clock settings of the VM which is disabled by default which you can see using following command.

Output of the above command is “0″ which shows that independent clock settings for the VM is disabled. Now use following command to enable it

and verify if its enabled or not

Now try to set the date and time using date –set or date -s command.