How can we handle captcha in Load Runner?

CAPTCHA (an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart") is a type of challenge-response test used in computing to determine whether or not the user is human. The term was coined in 2003 by Luis von Ahn, Manuel Blum, Nicholas J. Hopper, and John Langford.

The purpose of the CAPTCHA is to defeat the automation. CAPTCHA are based upon the turning test and as such the main purpose is to differentiate human from machine. Pattern recognition, vocal, visual (dynamic/static) has been broken several time. Much of the time it become a pain for the end-user, because they are a pain to decipher. Cultural reference or social pattern could be proven useful, achieve the same purpose and be less annoying for your customer

If you want to script the application which has CAPTCHA with the load runner you have to get the below things from the DEV.

• To disable CAPTCHA validation
• To make the CAPTCHA as static
• To remove the CAPTCHA
• To send the CAPTCHA value in server response(So that you can correlate)
• Provide the CAPTCHA details which are comes in the data base sequentially.

SSL received a weak ephemeral Diffie-Hellman key. (Error code: ssl_error_weak_server_ephemeral_dh_key) resolved

while recording any application with the load runner,or some times running in to manually we may get the below error in mozilla firefox.

Secure Connection Failed
An error occurred during a connection to consoleeset.soges-tech.ca:8443. SSL received a weak ephemeral Diffie-Hellman key in Server Key Exchange handshake message. (Error code: ssl_error_weak_server_ephemeral_dh_key)
The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
Please contact the website owners to inform them of this problem.

Solution for the above problem:

• Type about:config in the address bar of mozilla firefox
• search for security.ssl3.dhe_rsa_aes_128_sha and security.ssl3.dhe_rsa_aes_256_sha
• Set them both to false by double clicking on it.

WHAT IS A REVERSE PROXY SERVER?

A proxy server is a go-between or intermediary server that forwards requests for content from multiple clients to different servers across the Internet. A reverse proxy  server is a type of proxy server that typically sits behind the firewall in a private network and directs client requests to the appropriate back-end server. A reverse proxy provides an additional level of abstraction and control to ensure the smooth flow of network traffic between clients and servers.

Reverse proxy server benefits:

1.Load balancing: A reverse proxy server can act as a “traffic cop,” sitting in front of your back-end servers and distributing client requests across a group of servers in a manner that maximizes speed and capacity utilization while ensuring no one server is overloaded, which can degrade performance. If a server goes down, the load balancer redirects traffic to the remaining online servers.

2.Web acceleration:Reverse proxies can compress inbound and outbound data, as well as cache commonly requested content, both of which speed up the flow of traffic between clients and servers. They can also perform additional tasks such as SSL encryption to take load off of your web servers, thereby boosting their performance.

3.Security and anonymity :By intercepting requests headed for your back-end servers, a reverse proxy server protects their identities and acts as an additional defense against security attacks. It also ensures that multiple servers can be accessed from a single record locater or URL regardless of the structure of your local area network.

nslookup for multiple servers with a single click.

Nslookup is a command testing and troubleshooting the DNS servers.

Nslookup can be run in two methods.They are interactive and noninteractive. Noninteractive mode is useful when only a single piece of data n eeds to be returned.

Syntax: nslookup [-option] [hostname] [server]

some times it may need to get the dns details for the large number of servers at that time we need to run the command multiple times and capture the values each and time we hit the command.

To simplify this situation i have found an interesting too named as dnsdataview tool.
You can nslookup multiple number of servers at a single click with the clean GUI.

Download the tool here:

http://www.nirsoft.net/utils/dnsdataview.zip

Reference: http://www.nirsoft.net/utils/dns_records_viewer.html