Bashscript

 Basic Aws- interview Question  1)     How are Spot Instance, On-demand Instance, and Reserved Instance different from one another?   Both Spot Instance and On-demand Instance are models for pricing. Spot Instance On-demand Instance With Spot Instance, customers can purchase compute capacity with no upfront commitment at all. With On-demand Instance, users can launch instances at any time based on the demand. Spot Instances are spare Amazon instances that you can bid for. On-demand Instances are suitable for high-availability needs of applications. When the bidding price exceeds the spot price, the instance is automatically launched, and the spot price fluctuates based on supply and demand for instances. On-demand Instances are launched by users only with the pay-as-you-go model. When the bidding price is less than the spot price, the instance is ...

  AWS Linux instance connection     Now that putty has been configured to use a proxy and a private key you can try to connect to the server hosted in the Amazon Cloud.By default, the username that you will have to use to connect to the server hosted in Amazon Cloud and to which the RSA key is associated to is the ec2-user.At the login prompt enter ec2-user for username and you will be prompted to enter the Key passphrase that you have set for the private key that you have generated with puttygen.exe.Now that you have access to the server, you may wish to set the remote access for root.Use: sudo passwd root to generate a new password for root, then use su root to become root and change the configuration settings for ssh.Run vi /etc/ssh/sshd_config, set PermitRootLogin yes, PasswordAuthentication yes,  save the file, run service sshd restart and from now on you should be able to login to the server using the root, without using any previous RSA key or the ec2-us...