If you are a Linux newbie and if you are used to Amazon EC2 or any other VPS control panels, Google Compute Engine terminal system will be confusing for you. Google Compute Engine uses Google’s own tool called gcutil tool to manage Compute Engine and its resources. Not only using it but configuring it is bit hard for the newbies. And you wont ever need that if you are just running one or few VMs and not going to unleash the total abilities of Compute Engine.

There is no way to set a root password’s on VM’s from the Console like you do on control panels like SolusVM but you can use SSH keys to access the terminal without ever touching gcutils. Here’s how to do it,

Create SSH key pair

First we need to create SSH key pair on our computer. On this guide I’ll detail how you can do this on a Linux desktop or MacOSX, I don’t have access to Windows computer at the moment to explain it on Windows. However generating key pair on Windows is very easy. Use Puttygen, Google will find you many tutorials about that.

Log in to your Ubuntu desktop or any other Linux or OSX computer that you use to access the Compute Engine VM’s. Open up the terminal.

If you never generated SSH keys before, follow the guide below. If you have generated keys before to use on any other services and never saved the keys on a safe place, entering below commands will overwrite your keys so backup the old keys first or you will loose access to previously configured servers.

Open up the terminal of your desktop/workstation and enter below command to generate keysssh-keygen -t rsa
This will generate RSA crypto SSH keys for you and it will ask you where to save it, You can leave the default location and press enter, If your system already have configured keys it will ask to overwrite, press”y” and enter. When it asks for passphrase enter a strong password.

Now keys are generated. To view your public and private key just type

and

Of course you need to replace the above commands with your own commands which are mentioned when you were generating the key.

Now you need to save these keys on a safe place because if you loose these keys, you will loose access to your VM. So copy and paste these keys to text file and save it on a safer and secure place.

Setup SSH keys on Compute Engine Console

Its easy to setup SSH key based access on Compute Engine console. When you are creating the new instances you need to specify they keys as metadata like shown below

Enter “sshKeys” on the first box of metadata and on the second box you need to add your user name that you wish to setup on the server and the public key like below and follow the normal creation process.

ruchira: ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCicJSPZ0nnpo2nXfNFHdrnduGhsf7fTGDkLGhzboX8AEUqk1vyA2NMr5RhlAsqobeNjMwgzsKu8yt5vKTSr/ohWDXP3YeOzLUDslS24esG2abkBTPt5dNKOcdBH1O0pvwznNLPsPzy1lqQJCywmu/bBOyfuuzlfIgsEgbKCrOLg96ju3WqriwTrCz3V8zn5DeNZSpcX7VZjm8vkoAqDNVkLhPq0he6n6tBZg7fP0Euzt3Ug8OHVaTpYLtdXzu6HemVn0jx/7WqJELiKw6QFTW3CsYlekyiUgxoETMBBGuGa/W5ZmfDoQTFCvNfwZYxw+1RkWRuFJtM9nJuhyRrY2rF ruchira@PC

Congratulations you have just setup SSH key based access on Google Compute Engine. Now you can access your VM by your desktop’s terminal with the user name that you have specified on metadata. Just

And it will take you to your VM’s terminal console.

The post How to setup SSH key based access on Google Compute Engine appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

Google has announced immediate availability of Google Compute Engine to the general public at the Google IO 2013. Google Compute Engine is Google’s answer to the Amazon EC2 and other cloud platforms and it lets you to run virtual machines just like Ec2 with multiple configuration options. Compute Engine instances are based on KVM virtualization whereas EC2 is based on XEN. I have decided to signup and see whats inside

Signup page is here and we have to start by adding billing information. Credit Card is required to signup and after signing up, you are immediately taken to the Compute Engine Console where you can create and manage instances and disks.

You can define firewall templates and disk images prior to creating the instance. Console is very simple than the Amazon EC2 console and after selecting the instance size and OS image it creates the instance faster than the EC2 does. Availability of OS images are limited to Centos and Debian.

I’ll do another write up later about getting started with Compute Engine and adding SSH keys etc. I have created the smallest instance available which is named f1micro and it comes with 600MB RAM and access to 1 core.

Here are some of the benchmarks I done,

Connectivity and Disk IO benchmark 

Network speeds is average when comparing with the 1Gbps hosts out there but as you can see its fairly consistent on all around US. Its not surprising when thinking about Google’s network. Disk IO is not that good but this is what we should expect from these small instances. Also keep in mind that this isn’t local storage, Google is using SAN to power the persistent images. But you can use scratch disks ( local storage ) while you are creating the instance but its not recommended by Google , Here is the disclaimer that you get when you try to use scratch disks

I’m currently running the serverbear benchmarks on this instance and it seems that this will take very long time I’ll update this post when it finishes.

Update : After about 1.5 hours Serverbear test is finished. View the results here . UnixBench scored 410 marks which is poor but its comparable with Amazon’s micro instance. IO latency is good for a SAN setup but read/write speeds aren’t that good.

I hope to write more about how you can get started on Google Compute Engine and start hosting web sites with ease. Please stay subscribed.

The post Google Compute Engine benchmarks appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

Auto installers are designed to make your life easy. Installing and configuring things like Nginx and OpenVPN can be hard for novices. You can use the Nginx Autoinstaller listed on my blog if you need that, but what about OpenVPN? OpenVPN-AS is free and comes with a great web based control panel, but the problem is that the free version is limited to 2 concurrent users. But that’s the way to go if you are fine with 2 user limit, You can view my OpenVPN-AS setup guide here.

If you don’t like the 2 user limit on OpenVPN-AS you can install regular OpenVPN but it requires little bit of work, it has no limits on users and you and your friends or clients can use the same VPN concurrently. I have found a great OpenVPN auto install script on github and I thought about sharing it with you. You can find it here  installing it is very easy. See below

Requirements

• VPS or Dedi with 64MB of RAM or above
• TUN/TAP enabled if its OpenVZ ( see below )
• Debian , Ubuntu or any Debian derived distros are supported

Installing

If you are using a OpenVZ VPS make sure to enable TUN/TAP from your VPS control panel like below

Log in to the terminal and run the below command to download the installer and install

While its running it will ask for simple details such as the port you want to run , your name to generate the certs,

Answer to the questions and you are done, After it finishes installing it will display the success page

That’s it. Now you can SCP or SFTP ( here’s how to SFTP with filezilla ) in to your server and download the client config file from the /home directory.

Extract the file and you will find the certs and keys that you need to use to connect.

Adding more users

Adding more users to this is very easy just run the installer again

Simple! Isn’t it?

The post OpenVPN Auto installer appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

Are you using a DSL modem/router to connect to the internet? Mostly everyone I found haven’t changed the default user name and password which is used to login to the modems admin panel. Most modems comes with the default user/pass combination of admin/admin , admin/password. So what is the risk of not changing these logins?

Most of the older modems and around 20% of newer modems doesn’t have a firewall ( or disabled firewall option by default ) between the internet and the modem. So this means that anyone who knows your public IP can login to your routers admin panel and do potentially dangerous stuff. Including stealing your DSL services login names ( most common ) , opening up ports to give access to run malicious programs etc.

How the hackers find your IP’s 

Lets say that I want to steal DSL service login details from the people who use the same DSL service that I use. There are 2 simple methods to do that

• Ping the IP range of the provider

You can find the IP address ranges of the provider by using a service like http://bgp.he.net . When you visit that link you can find the AS ( Autonomous System ) of your current IP range and see whats IP ranges that your ISP is announcing. Or you can search for the provider and find the ranges. Now I can ping that range to find the IP’s addresses which are currently responding and after finding the IP’s which are currently up, I can try entering those in my web browser and when it prompts the login dialog I can try the default combinations.

• By using an IP logger

It’s very easy to capture the IP’s by using a service like http://iplogger.org . hackers just have to insert the hidden image on local community forums, blogs and places where the people gather and in a moment hacker will have 100′s of probably alive IP’s at his disposal.

Be smart change login details now

I’m not a hacker by any means but I have tried the second method mentioned above to experiment on this and I was surprised to find that even some modems let you telnet to it by using the public IP. The most common abuse done by the hackers is stealing the login details to DSL service so they can use your login details to do the all kind of abuse such as consuming your bandwidth allowance and launching attacks.

You can avoid these attacks by enabling the default firewall of the modem and changing the login details. So if you haven’t already, do this now!

The post Change your DSL modems default logins now or get hacked appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

When I was browsing through my new email account, I have saw the above email from Paypal saying my account is limited because of a identity issue? This email account is new and I didn’t used it much at all, And surprisingly this email was on my inbox not spam folder. I thought my Paypal account is limited and to verify that I opened up paypal.com on a new tab and logged in. And there was no limitations or whatsoever like said on the email. It didn’t took me much time to recognize that, this is indeed a phishing attempt. So this is what I found,

Real sender of the email is hon@hon.com and he/she has masked the address to intel.service@paypal.com, And returning path is also hon@hon.com. I have opened up the attachment and its a html page which looks like this 

Interesting right? So I have looked at the source code of the html file and its encoded with javascript unescape() string. Its really a large amount of code there which froze my web browser when I tried to decode it using a web service. With the help of this online decoder I was able to decode the encrypted code and here is the interesting part,

All the other content such as css files are pulled from the real paypal.com and this is the only suspicious part on the code. That IP address belongs to a digitalocean VPS customer. These script kiddies might be signing up on digitalocean using free credits provided by them all over the internet and just abuse the service. I have informed digitalocean but that IP address is offline since I found this.

So moral of the story is that, if you receive this kind of emails asking you to login or do something by clicking the provided link, don’t ever do that. Just open up the mentioned services web site on a new browser window and check it.

The post Just another Paypal phishing attempt appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

http://sphotos-a.ak.fbcdn.net/hphotos-ak-ash4/420176_10150632396635768_2036862295_n.jpg

See the link above? Yes its a direct link to a Facebook photo as most of you might have recognized at the first glance. You can see these links everywhere, or your friend might send you this type of direct link to a Facebook photo because He/She doesn’t want to know the profile of the person who posted the photo to the Facebook. So is there any way to find the profile of the person who owns the photo?

Yes you can.  Its very easy so don’t do that same mistake again by sending the direct link to an image if you are concerned about privacy. Let’s see the aforementioned link again

http://sphotos-a.ak.fbcdn.net/hphotos-ak-ash4/420176_10150632396635768_2036862295_n.jpg

Notice the last part of the link which is after the last trailing slash

Numbers in the middle of this part represents the owner of the photo

Copy that part and visit www.fb.com/X on your web browser , Replace the X with the number,

Voila!

The post Find the Facebook profile from a direct image link appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

If you are using a USB HSPA dongle to access the internet, one of common problem that you might face is the low signal strength on the place that you live.  Low signal levels translate in to low download/upload speeds and higher latency. The level of signal’s depend on various factors such as the distance between you and the nearest transmission tower of your service provider etc. But there are some ways that you can use to increase the signal levels that your modem receives,

Place the dongle outside

This is the simplest method to increase the signal strength. HSPA modems works the same way as your mobile phone. So this means some places on your home will have better reception. If you don’t have the liberty to move your computer around, best way is to buy a long USB extension cable and use that to place your modem outside of your house or inside where good amount of reception is available.

Extension cables are really cheap and you can find those on most of local computer parts shops or Ebay. Here is one on ebay, for just under $5 including shipping you can get a decent extension cable.

Buy an External Antenna 

Almost all of Huawei and ZTE HSPA dongles that I know supports external antennas. Not only the USB dongles but the data cards supports external antennas too.

This is the most effective solution to increase the signal strength. But a decent antenna like pictured above costs about $20 online . But it can be a nice investment if you are dependent on HSPA modems to access the internet. Before you buy don’t forget to check if your dongle has a port to connect external antennas, this is mentioned on the manual and online product pages.

The post How to increase signal strength of HSPA dongle appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

Do you remember the webmaster outrage happened after the Google Panda update which was rolled out April 24th last year? Until now Google has been rolling out lots of small incremental updates to the search algorithm, beating bad web sites to the ground and also affecting some percentage of genuine web sites too. If you have a spammy link profile you probably should be already affected by these updates. I have wrote earlier about how you can disavow spam links pointing at your web site. But that’s just a part of the equation.

Matt Cutts recently tweeted that they are going to deploy Penguin 2.0 update within next few weeks,

So Penguin 2.0 will probably roll out within this month or next month for sure. So if you are concerned about your traffic you should stop participating on link networks and stop other sorts of blackhat ways to build links. Google loves quality and unique content, focus on that.

The post Google Penguin 2.0 is rolling out soon appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

“Shield” is the Nvidia’s approach to the handheld gaming market. Few minutes ago Nvidia has announced the pre-order availability. Nvidia Shield is now available to pre-order from NewEgg , GameStop and Nvidia’s own web store for just $349.99. Release data is mentioned as 06/04/2013

Shiled concept is not ground braking at all, Its just an Android gaming device but the bright side is that it will attract many game developers than for the small Android game device manufacturers. Also Nvidia Shield is one of the first devices to use Nvidia’s latest  Tegra 4 processor and here are some specifications listed on Newegg,

Processor
NVIDIA Tegra 4 Quad Core Mobile Processor with 2GB RAM

Display
5 inch 1280×720 Multi-Touch Retinal Quality Display

Audio
Integrated Stereo Speakers with Built-in Microphone

Storage
16GB Flash Memory

Lid color
Silver

Wireless
802.11n 2×2 MIMO Wi-Fi
Bluetooth 3.0
GPS

Connectivity
mini-HDMI output
micro-USB 2.0
microSD storage slot
3.5mm stereo headphone jack with microphone support

Motion Sensors
3 Axis Gyro
3 Axis Accelerometer

Battery
28.8 Watt Hours

Operating System
Android Jelly Bean OS

It would be nice if the display is 1080P comparing with the latest standards but game devices are normally held at a distance where you cant notice any difference between 720P and 1080P and battery and resource usage will be lower with 720P as well. So really cant blame Nvidia for that.

Looking at the released photos, it looks like its running stock version of Android jelly bean. Tegra Zone is added to download games from Nvidia’s own Tegra specific store. Shield has the potential to be a successful gaming console but only the time will tell fore sure.

The post Nvidia Shield is now available for pre-order appeared first on Ruchirablog | Ruchira Sahan's Weblog!.

You might know about the Nginx Auto install script listed on this blog . Its been almost 3 years since I have released my first modified version of it. Those days my version brought a lot of changes to the original version because my version came with the latest versions of Nginx , PHP.  But later on the original developer Incorporated most of my changes to the original version.

Today I have released the newest version of the Nginx auto installer bringing some minor changes,

• Nginx 1.2.9 by default ( you can always upgrade using instructions )
• Removed the server probe ( a script which was used to display server information on a web page ) because of security concerns
• All files are now hosted on this blog
• Removed china timezone rewrite

If you are already using the script, there is no need to upgrade. But delete the /p.php file from your wwwroot directory for maximum security. Visit http://www.ruchirablog.com/nginx-autoinstaller/ for more details

The post Nginx Auto Installer minor update appeared first on Ruchirablog | Ruchira Sahan's Weblog!.