Fixing Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool.

We are getting following error in our application.

Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.

If you want to find out what is eating up your connections, try this:

  1. Implement correctly all connections inside using blocks to close/dispose connections (as you said, this is already done)
  2. Check which user/machines are keeping opened connections. Run this query to identify the database id:

select distinct dbid, DB_NAME(dbid) FROM sys.sysprocesses where dbid > 0

Then, use this query to inspect all opened connections, replacing the dbid:

SELECT dbid, DB_NAME(dbid) as DatabaseName, COUNT(dbid) as ConnectionCount, loginame as LoginName
  FROM sys.sysprocesses
 WHERE  dbid = 1
 GROUP BY dbid, loginame
 ORDER BY count(dbid) desc

This can give you some hint about who is keeping too much connections opened.

  1. Implement pooling in connection string to limit connections. Use this in your application connection string:

Pooling=true; Min Pool Size=1; Max Pool Size=5


SQL Injection for beginners

When we talk about security vulnerabilities in software it’s worth thinking about computer programmes on a fundamental level. On the simplistic level a computer programme is something which takes in an input, usually from the user in the form of text, processes that input, which changes the state of the machine, and then gives as output or result to the user. A bug is when certain inputs aren’t processed correctly and the wrong output is given. For example, if 1 plus 1 results in 3. A security bug however, can be when a certain input is processed in such a way that compromises the security of information managed by a programme and may even output it. We often see this in practice in web applications. Continue reading “SQL Injection for beginners”

Set up SMS for Two-factor authentication with Twilio

Adding two-factor authentication (2FA) to your web application increases the security of your user’s data. Multi-factor authentication determines the identity of a user in two steps:

  • First we validate the user with an email and password
  • Second we validate the user using his or her mobile device, by sending a one-time verification code

Once our user enters the verification code, we know they have received the SMS, and indeed are who they say they are. This is a standard SMS implementation. Continue reading “Set up SMS for Two-factor authentication with Twilio”

Login page password-guessing attack (Accunetix)

A common threat web developers face is a password-guessing attack known as a brute force attack. A brute-force attack is an attempt to discover a password by systematically trying every possible combination of letters, numbers, and symbols until you discover the one correct combination that works.

This login page doesn’t have any protection against password-guessing attacks (brute force attacks). It’s recommended to implement some type of account lockout after a defined number of incorrect password attempts. Consult Web
references for more information about fixing this problem.

CVSS Base Score: 5.0
– Access Vector: Network
– Access Complexity: Low
– Authentication: None
– Confidentiality Impact: Partial
– Integrity Impact: None
– Availability Impact: None
Affected item /Admin/Login.aspx
Affected parameter
Variants 2

Blocking Brute-Force Attacks

A common threat Web developers face is a password-guessing attack known as a brute-force attack. A brute-force attack is an attempt to discover a password by systematically trying every possible combination of letters, numbers, and symbols until you discover the one correct combination that works. If your Web site requires user authentication, you are a good target for a brute-force attack. Continue reading “Login page password-guessing attack (Accunetix)”

Using the configuration Builder in ASP.NET 5

The Problem

Managing the configuration data have always been troublsome. Although Microsoft did provided and also updated/upgraded a lot of options from time to time, yet it remains  a challenge most of time. Things get more critical when the configuration data we are concerned is the confidential data like connection string, smtp passwords, API keys etc becase at some point of time, they do get checked in source code or shared across other developers. In one of my prev project faced a similar issue when private key and the Code Signing certificate was accidentally checked in by a developer. The customer had to revoke the certificate which invalidated all the production builds which were deployed to end users as well. Continue reading “Using the configuration Builder in ASP.NET 5”

How to make your first WebAPI2 Project

With the introduction of OWIN  and self hosting, microsoft has really opened a lot of possible doors for developers and application users. This post is targetted to have an OWIN application hosted in Windows Service. Also we would be configuring the SSL for the Site.

Creating a Windows Services Project

This is pretty straightforward. In visual Studio, Create new project and select Windows Service as project. This will add a project with default Service “Service1”. Rename to whatever the name expected. Continue reading “How to make your first WebAPI2 Project”