You don’t need any database or snmp connection to monitor all of your client with bandwidthd an open source application for monitoring bandwidth usage on Apache and IIS. All you need just libcap, libpng, libgd and apache/IIS installed on your Linux/Windows system and you can monitor all your connected clients per IP and per connection protocol.

Installation and configuration in windows

Download the packages below and install them prior to installing the bandwidthd software

For installing gd-latest extract the zip archive and place it in a directory in C drive say “gd”. Navigate to the directory C:\gd\bin and copy the bgd.dll to c:\windows\system32 directory.

  1. Download the “Bandwidthd” software from the link
    http://sourceforge.net/projects/bandwidthd/files/
  2. Extract the zip archive and place it in a folder say c:\inetpub\bandwidthd.
  3. In IIS create  a virtual directory either to your existing website or under the default website and point the home directory to “C:\Inetpub\bandwidthd\htdocs”.
  4. Open the file C:\Inetpub\bandwidthd\etc\bandwidthd.conf and  provide the correct subnet of your network.
  5. Now navigate to the directory C:\Inetpub\bandwidthd and execute the batch file “Install Service.bat”. This will install a service for bandwidthd. Make the service start up type as automatic and start the service.
  6. Now point your web server as http://<server IP>/bandwidthd and you will now be able to view the graphs containing the bandwidth statistics.

Installation and configuration in Redhat/Centos/Fedora Linux

  1. As a prerequisite please ensure that you have libcap, libpng, libgd and apache installed in your computer.
    # rpm -qa | grep libcap
    # rpm -qa | grep libpng
    # rpm -qa | grep gd
    # rpm -qa | grep httpd
  2. Next download the bandwidthd RPM according to your Linux distro from the link
    http://rpm.pbone.net/index.php3 (Search with “bandwidthd”)
  3. Install the RPM as below
    # rpm -ivh bandwidthd-2.0.1-9.el5.i386.rpm
    This will install bandwidthd under /var/www/bandwidthd
  4. Next open the httpd.conf file
    # vi /etc/httpd/conf/httpd.conf
    Add the lines as below to it and save:

    Alias /bandwidthd “/var/www/bandwidthd/htdocs”
    <Directory “/var/www/bandwidthd/htdocs”>
    Order Allow,Deny
    Allow from All
    </Directory>

  5. open /var/www/bandwidthd/etc/bandwidthd.conf and provide the correct subnet for your network.
  6. Restart the webserver
    # service httpd restart.
  7. Start the bandwidthd service
    # service bandwidthd start
  8. Now point your browser to http://<server IP>/bandwidthd and start checking the bandwidth statistics graphs.

Few screenshots

Posted by anirban under Virtualisation
0 Comments

Virtualisation Hosting Services

Virtualisation alongwith cloud computing are the hottest buzzwords in the online IT world today. Both these technologies are very promising and on a long term basis it would help lower the TCO (total cost of operation) for the consumers and ensure a scalable service infrastructure where the underlying hardware becomes a virtualised commodity.

At Diadem, we like to be on the leading edge by deploying these technologies on our network infrastructure and enable our clients to benefit from such services. Our Virtual Private Server offerings is the result of over six months of dedicated effort in research, testing and deployment to enable implementation of stable, reliable and cost effective VPS offerings for our clients.

So what is a VPS and why do I need one?

Virtual Private Servers is an offshoot of OS virtualisation, which allows you to run more than one operating system simultaneously or singly on a single machine by sharing the same hardware resources. While OS virtualisation has been existence since the 1960′s, it has evolved rapidly over the past decade, thanks to the explosive growth of the Internet requiring ever more servers online and the need by businesses to cut down their  IT spend and consolidating multiple OS for different functions, within a single server. Server virtualisation is now a proven and accepted technology which enterprises of all shapes and sizes are embracing rapidly for their server deployment needs to ensure that their server infrastructure is well utilised and generate a higher ROI from their IT investments.

Here is my non technical description of a VPS:

“A Virtual Private Server is a ‘server within a server’ which allows you to have your own memory space, HDD capacity and CPU resources and enables you to run your own Operating System within a dedicated server. Consider it to be your own apartment within a multi-storied building. Every apartment owner has their own living space, bedrooms and other areas which they could beautify and update as per their individual needs but they also share a common entrance to the building with the rest of the apartment owners, a common heating and sewage system, electrical wiring and other such features to reduce the cost of the apartment per individual.”

Benefits of a VPS in comparison with dedicated servers or shared hosting is highlighted below:

  • A virtual server is significantly cheaper to run than a standalone dedicated server in which an entire server is dedicated for a specific client.
  • It allows clients to experiment their application on a smaller scale without having to make upfront investments on a dedicated server.
  • Businesses can run multiple servers with different operating systems from within the same physical server, thereby reducing the cost and increasing the utilisation of a dedicated server.

Compared to a shared hosting environment, here are the key benefits of a VPS:

  • It is a secure environment dedicated for the client to run their websites online and retain complete control on the server.
  • Server OS settings can be tweaked and optimised as per the requirement of a specific application.
  • Corporates can run their own mailing servers in a secure VPS which would allow them to create unlimited email ids, web space for individual users with customised antispam and mail archiving solutions.
  • Clients can consolidate multiple sites on a single VPS and manage them from a single OS.
  • Web design firms can operate their own hosting services without having to share credit with a web hosting firm.

Our VPS Story

While we have been dabbling with virtualisation for the past year, we seriously got into delivering it as a service to our clients towards the end of last year. There were three main contenders for the virtualisation platform, Windows HyperV, VMWare ESXi and Citrix XenServer and we gave them a fair evaluation from our end.

While each server virtualisation platform has its own pros and cons and new features are being developed and deployed for all these hypervisors on a rapid scale, we found Citrix XenServer to be the most suitable for our needs. Following are the primary reasons why we choose XenServer over the other hypervisors:

  • The Citrix XenServer is FREE for personal and commercial use.
  • It is packed with tools and features which are available as paid options or are non existent in other hypervisors.
  • Citrix XenServer is based on the industry standard Xen hypervisor which is an open source virtualisation platform.
  • There is a large community backing Xen and it is a well documented system.
  • It has a small memory footprint which makes it less resource intensive on the server.
  • It is stable, easy to deploy and is supported by Citrix Systems which is a leader in virtualisation technologies.

Now that we have done the heavy lifting in putting our virtualisation infrastructure in place, we would like you to benefit from our VPS offerings, which is available in both Linux and Windows platforms. Checkout our Linux VPS and Windows VPS plans which are specially developed considering the requirements of the Indian market and are available from a low monthly cost of Rs. 1999 per month.

We would be putting up more resources, howtos, offers and updates highlighting our VPS services over the next few months so watch this space!

1 Star2 Stars3 Stars4 Stars5 Stars (No Ratings Yet)
 Loading ... Loading ...

Posted by hriday under Virtualisation
2 Comments

For businesses considering our dedicated server options, one of the questions you’ll need to answer about your server configuration is whether to utilize a RAID disk configuration or not.  For our shared hosting customers, all of our shared server hardware utilizes a RAID disk configuration as a measure to help ensure maximum server uptime. With a single hard disk, you cannot prevent a significant downtime against a disk failure, which includes:

  • The time required to obtain and install a replacement disk
  • Reinstall the operating system
  • Restore files from backup locations and
  • Restore all the data entry performed since the last backup was made.

With multiple disks and a suitable redundancy scheme, your system can stay up and running when a disk fails, and even while the replacement disk is being installed and its data restored.

An Overview of RAID

RAID stands for Redundant Array of Independent Disks.  The purpose of RAID is to provide redundancy for hard drives in the event that a hard drive is lost due to mechanical failure.  Hard drives are the most susceptible component in a server to fail, just by the nature of it’s design.

RAID solves this problem by copying data from one drive to another in real time.  For every bit that is written to one drive, it’s also written to it’s “mirror” counterpart.  So, in the event that one drive is lost, the other drive is available to continue reading and writing data without any interruption to the server.

RAID 0 (Striped Disk Array without Fault Tolerance)

A non-redundant disk array, or RAID level 0, has the lowest cost of any RAID organization because it does not employ redundancy at all. This scheme offers the best performance since it never needs to update redundant information. Surprisingly, it does not have the best performance. Redundancy schemes that duplicate data, such as mirroring, can perform better on reads by selectively scheduling requests on the disk with the shortest expected seek and rotational delays. Without, redundancy, any single disk failure will result in data-loss. Non-redundant disk arrays are widely used in super-computing environments where performance and capacity, rather than reliability, are the primary concerns.

  • Does not provide fault tolerance
  • Minimum number of disks required = 2
  • Usable storage capacity = 100%
  • This is the fastest of the RAID configurations from a read-write standpoint
  • Is the least expensive RAID solution because there is no duplicate data
  • Recommended use for temporary data only

RAID 1 (Mirroring)

The traditional solution, called mirroring or shadowing, uses twice as many disks as a non-redundant disk array. Whenever data is written to a disk the same data is also written to a redundant disk, so that there are always two copies of the information. When data is read, it can be retrieved from the disk with the shorter queuing, seek and rotational delays. If a disk fails, the other copy is used to service requests. Mirroring is frequently used in database applications where availability and transaction time are more important than storage efficiency.

  • Fault tolerant – you can lose multiple disks as long as a mirrored pair is not lost
  • Minimum number of disks required = 2
  • Usable storage capacity = 50%
  • Good read performance, relatively slow write performance
  • Recommended for operating system log files

RAID 5 (Block Interleaved Distributed Parity)

Consists of three or more hard drives.  RAID 5 requires a minimum of at least three (3) drives.  Redundancy is provided by “striping the parity” across all drives.  This means that any one drive contains the “redundant” information.  If one drive is lost, the other two drives continue reading and writing data without any interruption to the server.

  • Fault tolerant – can afford to lose one disk only
  • Minimum number of disks required = 3
  • Usable storage capacity = subtract 1 whole disk from the total number in the array (i.e. 3 60Gig hard drives would provide 120Gig of usable disk space)
  • Generally good performance, and increases with concurrency – the more drives in the array the faster the performance
  • Recommended for operating system files, shared data, and application files

RAID 10 (A Stripe of Mirrors)

RAID 10 uses more disk space to provide redundant data than RAID 5. However, it also provides a performance advantage by reading from all disks in parallel while eliminating the write penalty of RAID 5. RAID 10 requires a minimum of at least four (4) drives In addition; RAID 10 gives better performance than RAID 5 while a failed drive remains unreplaced. RAID 10 offers faster data reads and writes than RAID 5 because it does not need to manage parity. Under RAID 5, each attempted read of the failed drive can be performed only by reading all of the other disks. On RAID 10, a failed disk can be recovered by a single read of its mirrored pair.

  • Fault tolerant – you can lose multiple disks as long as both are not part of a mirrored pair
  • Minimum number of disks required = 4
  • Usable storage capacity = 50%
  • Generally good performance, and increases with concurrency – the more drives in the array the faster the performance
  • Recommended for operating systems, shared data, application files, and log files

We would recommend RAID 10 to all dedicated server owners for performance, uptime and disk redundancy. You do lose 50% of the total cumulative disk capacity, but the performance, redundancy and security of data makes up for it.

To know more about our RAID Hosting services and how your business would benefit from it, visit our RAID Hosting Services page.
1 Star2 Stars3 Stars4 Stars5 Stars (No Ratings Yet)
 Loading ... Loading ...

Posted by hriday under Web Hosting
0 Comments

The big boys of the free email world, namely Google, Yahoo and Hotmail have zero tolerance towards users who abuse their mail accounts and use it to send UCE (unsolicited commercial email) to other email users. Here are a list of links which can be used to report such spam incidents so that their accounts can be permanently disabled by these providers.

Feel free to share any other resources which can be of use to report spam to other such providers of free email services.

1 Star2 Stars3 Stars4 Stars5 Stars (No Ratings Yet)
 Loading ... Loading ...

Posted by hriday under Web Hosting
0 Comments

If you want to redirect all incoming TCP traffic on port 80 to a custom port say 8089 on the local machine, then xinetd is a good option. Xinetd, the Extended Internet Daemon, is an open-source super-server  daemon which runs on many Unix-like  systems and manages Internet-based connectivity.

Follow the below steps redirect to the 80 port.

Login to your Linux server as super user i.e. ‘root’.

Create a file under /etc/xinetd.d/ folder as http_redirector

# vi /etc/xinetd.d/http_redirector

Now add the following entries in the files.

service http_redirector
{
type = UNLISTED
disable = no
socket_type = stream
protocol = tcp
user = root
wait = no
port = 80
redirect = 127.0.0.1 8089
log_type = FILE /tmp/httpredirector.log
}

Restart the xinetd service.

# service xinetd restart

That’s all you are done.

Posted by ankur under Linux, Web Hosting
0 Comments

power backup solution for diademThis year, I am expecting a power crisis in Kolkata for the following reasons:

  • Summer has crept in earlier this year and therefore ACs will start gobbling up energy sooner than expected.
  • Salt Lake, which was supposed to be a VIP area is not going to get preferential status with regards to power outages and would have to face the heat like the rest of the city.
  • Overall energy consumption has grown considerably over the past couple of years and would continue to soar. In comparison the supply of additional energy has crept at a slow pace and the deficit only seems to be widening.

Keeping the above factors in mind, we have invested in our own power backup solution, a Honda 2.8 KVA diesel powered generator which should keep our office humming with activity in the event of a power outage or “loadshedding” as its more commonly known in the city.

We were earlier planning to install a large rack of batteries with an online UPS but it was a relatively expensive solution with limited power backup availability. It would have also taken up additional storage space in our office along with periodic replacement of batteries, i.e. higher maintenance costs.

We arranged for a demo of the Honda generators and the Honda salesmen were very efficient and prompt in handling our request and provided us with a live demo which ensured that it would run our PCs and office equipment and scale up as our load increases. This little baby is also environment friendly with restricted CO2 emissions and low running noise, so it should keep our neighbors happy as well!

This is a small step in our continued efforts to ensure that our support services are available round the clock for your business :) .

1 Star2 Stars3 Stars4 Stars5 Stars (No Ratings Yet)
 Loading ... Loading ...

Posted by hriday under News & Updates
0 Comments

RBL stands for Real-time Black-hole List, this is a term for DNS based systems designed to assist in the prevention of email abuse. The first such system was created by Mail Abuse Prevention System (MAPS) LLC. The generic name for such services is DNSBL.

The RBL usually lists server IP addresses from ISPs whose customers are responsible for the spam and from ISPs whose servers are hijacked for spam relay. The DNSBL consists of a DNS based system containing lists of IP addresses whose owners refuse to stop the proliferation of spam whether this is by running their mail servers as open relays, or by allowing their users free outbound access to port 25.

In the case of E-mail there are distributed projects on the Internet which monitor where spam mail is originating from and add these to a real time list which can be checked when deciding whether to accept or deny mail.

Most spam on the Internet originates from two places:

  • Virus/Trojan infected machines which appear to be running normally to a user but are also sending spam out to the Internet at large after being fed a list of addresses/spam e-mail from a remote operator.
  • Professional spammers. Who send spam out from their own systems up to any limits by ISP or any compromised mail server.

The RBL identifies these machines by their internet address and adds them to a list that can be checked in real time by an e-mail server. If a server has been listed as a spam host the mail will be refused immediately. This means less overhead on e-mail systems and a lot less spam for end users. It also generally means less “fake” bounce messsages that users receive when spam is forged to come from them.

As subscribers to the DNSBL, ISPs and companies will know from which IP addresses to block traffic. Most traffic blocking occurs during the SMTP connection phase. The receiving end will check the DNSBL for the connecting IP address. If the IP address matches one on the list, then the connection gets dropped before accepting any traffic from the IP address.

Below are the lists of few RBL/DNSBL sites.
SpamCop – http://www.spamcop.net/
The Spamhaus Project – http://www.spamhaus.org/
Mail Abuse Prevention System LLC – http://www.mail-abuse.com/
The Spam and Open Relay Blocking System – http://www.sorbs.net/
1 Star2 Stars3 Stars4 Stars5 Stars (No Ratings Yet)
 Loading ... Loading ...

Posted by ankur under Web Hosting
0 Comments

Paypal has recently stopped allowing Indian providers to receive funds from other paypal account holders and it is also voiding the withdrawal of funds by Indian establishments to their Bank A/c’s in India. This is a double whammy by Paypal as most small to medium web dev shops and freelancers in India depend on Paypal for receiving payments from their clients abroad.

Also, the way Paypal has handled this situation is a bit appalling. Rather than intimating the Indian account holders in advance and assuring them of a resolution, they are first reversing the received funds back to the users and *than* informing the sellers of this issue.

While I am sure Paypal is working hard to resolve this issue as they have the financial strength and their brand image to safeguard, this raises some valid questions on how reliable are these online service providers in India. If this can happen to Paypal, what stops Gmail, Facebook and other such online providers from blocking access to their services to Indians?

As these firms are operated from outside India and are not governed by Indian laws and regulations, their failure to comply with any present and future law and regulations in India, might force them to rescind their services to their users in India.

My advice for avoiding such a situation from adversely impacting your business would be to read the fine print for all such online services which your business depends on and have a Plan B in place in case these services are unavailable one fine morning, as in the case of Paypal.

Update: The head of Paypal APAC region has posted an update on this issue, whch can be viewed at www.thepaypalblog.com.
There has been quite a bit of criticism for the post on Paypal, which can be viewed on the EvenHorizon1984 Blog.

1 Star2 Stars3 Stars4 Stars5 Stars (No Ratings Yet)
 Loading ... Loading ...

Posted by hriday under Marketing Tips & Advice, News & Updates
0 Comments

In this post we will discuss on creating a custom block through a module in Drupal 6.  One question can come into your mind that we can create block from the administrative menu/site building/blocks. So, what is the need to create block from module.

The benefit of creating block from module is that, the module can be placed in any theme or in any other sites and once the module is enable the block will created automatically with its contents as we have configured in the module.

Some easy steps to create block through module :

Step 1 :

Create a folder (give a folder name e.g., mymodule) in the modules directory of your Drupal site.  The name which you are giving as a folder name will become your module name. To create a module there must have two files inside the module folder named as:

( a) mymodule.info (b) mymodule.module

mymodule.info file contains the general information of the module you created and mymodule.module file contains the main coding which creates the block.

# We are considering the module name as customblock and hence filenames are customblock.info and customblock.module

Step 2 :

Copy the code given below and paste it inside the customblock.info file.

; $Id: customblock.info,v 1.4 2009/02/18 22:02:46 dries Exp $
name = Custom Block
description = Creating Custom Block to demonstrate the block creation through module.
package = Diadem
version = VERSION

; Information added by drupal.org packaging script on 2008-10-08
version = “5.11″
project = “drupal”
datestamp = “1223496909″

This is the general information about the module and description field reflect the purpose of creating the module . Give the correct version which you are using for your drupal site. You need to change this information as per your requirement.

Step 3 :

Always remember that all the function name should start with the module name, e.g.  modulename_node_info(), modulename_perm(), etc. Copy the code given below and paste it inside the customblock.module file. You will observe that there has no php end tag at the end of the file. It is recommended in drupal that we donot need to end the php tag in the module pages.

<?php
/**
* Implementation of hook_node_info().
*/
function customblock_node_info() {
return array(
‘customblock’ => array(
‘name’ => t(‘Custom Block’),
‘module’ => ‘customblock’,
‘description’ => t(‘How to create a custom Block.’),
)
);
}

/**
* Access Permission of this module by hook_perm();
*/
function customblock_perm() {
return array(‘access customblock content’);
}

/**
* Implementation of hook_block().
*/
function customblock_block($op=’list’, $delta=0) {
// listing of blocks, such as on the admin/block page
if ($op == “list”) {
$block[0]["info"] = t(‘Custom Block’);
return $block;
}
else if($op == ‘view’)
{
$block_content=”;
$block_content.=’<div style=”border:1px solid #D6D6D6; background-color:#F2F2F2; padding: 5px;”>’;

$block_content.=’<div>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry\’s standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. Why do we use it? <br />
<a href=”http://drupal.org/” target=”_blank”>Click Here</a> – Drupal.Org
</div>’;
$block_content.=’</div>’;

$block['subject'] = ‘Custom Block’;
$block['content'] = $block_content;
return $block;
}
}

Explanation :

1)  customblock_node_info() : This is the implementation of the hook_node_info function defined in Drupal. This function contains the information about the module. E.g.: name which will show in the module listing page. Description – Some general information about the module and module – module name.

2) customblock_perm(): This is the implementation of hook_perm function defined in Drupal.

3) customblock_block() : This is the implementation of hook_block function defined in Drupal. This function is responsible to return the block content. You can see, we have defined a variable $block_content which contain the block with its contents and properties.

$block['subject'] variable contains name of the block created. Finally, we assigned the $block_content into the $block['content'] variable beacuse this varible is responsible to create the block.

step 4 :

Enable the customblock module from administrative menu/site building/modules.

mod

Custom Block Module

Once you enable the module a block named as Custom Block will be created . Configure the block from administrative menu/site building/blocks. Finally, place the block where you want to display in your drupal site.

Block
1 Star2 Stars3 Stars4 Stars5 Stars (1 votes, average: 5.00 out of 5)
 Loading ... Loading ...

Posted by mithun under CMS, Drupal CMS
0 Comments

Its been a while since we last updated our blog as we had been busy with some extensive repair and renovation work which we undertook within our office over the past month. Its been nearly a decade since we started our operations at the current premise and though we had undertaken some routine maintenance work every couple of hours, we felt the time was right to go in for a serious overhaul and roll up our sleeves.

Starting with a fresh coat of paint, new flooring, window blinds, carpentry and masonry work, we went on an overdrive to get everything completed before the New Year. Fortunately, the work progressed as planned and on Jan 01, 2010 we shifted back to our ‘Office 2.0′.

We are all extremely pleased with the results of our efforts and here are some pics of our revamped office for our clients and associates whom we may not have the good fortune to meet on a one to one basis.

Here are some takeaways which I gathered from this assignment:

  • Meet all the people who would work on this project (multiple times in advance) to ensure that they provide you with fixed quotes for the work and the scope of work has been agreed upon.
  • Keep a buffer of atleast 25% for time and cost overruns as some amount of scope creep is inevitable.
  • Ensure that all materials are bought in your presence (or someone you trust) to ensure that you get the right quality at a reasonable price.
  • Avoid contracting work to promoters as they tend to over inflate the cost by about 50% in comparison to working with individual specialists (carpenters, painters, etc.).
  • Create a project schedule (who will work on what and when) a week in advance and try to build in some amount of buffer between them. Create sub-tasks within a major task to break down all activities into small, unique tasks.
  • Pay on completion of agreed milestones.

My best wishes to you for a successful 2010 and at Diadem Tech we are excited with the opportunities and challenges which the New Year brings to us!
1 Star2 Stars3 Stars4 Stars5 Stars (2 votes, average: 4.50 out of 5)
 Loading ... Loading ...

Posted by hriday under News & Updates
0 Comments