Understanding Curl 35 TCP Connection Reset by Peer: An In-Depth Analysis


In the realm of web development, ensuring seamless data transfer and communication is paramount. One common issue that developers often encounter is the dreaded “curl 35 TCP connection reset by peer” error. This article delves into the intricacies of this error, shedding light on its causes, implications, and solutions.

What is Curl 35 TCP Connection Reset by Peer?

Before we dive into the depths of this issue, it’s essential to understand what “curl 35 TCP connection reset by peer” actually means. In simple terms, it’s an error message that occurs during data transfer using the cURL library, often experienced when interacting with web servers. The error message “TCP connection reset by peer” implies that the server at the other end abruptly terminated the connection.

Common Scenarios Leading to Curl 35 TCP Connection Reset by Peer

1. Network Instabilities

Network instabilities are a primary culprit behind this error. When there are fluctuations in the network, such as high latency or packet loss, the connection can be reset by the server to maintain stability. Developers need to be vigilant and consider the quality of their network when encountering this error.

2. Server Overload

In scenarios where the web server is overwhelmed with traffic or resource-intensive tasks, it may decide to reset connections to free up resources for other users. This can manifest as the “curl 35 TCP connection reset by peer” error, leaving developers scratching their heads.

3. Firewall and Security Measures

Firewalls and other security measures on the server can also trigger this error. If a request is deemed potentially malicious, the server may reset the connection to protect itself. This emphasizes the importance of configuring your requests and server settings correctly.

Troubleshooting Curl 35 TCP Connection Reset by Peer

So, you’ve encountered the “curl 35 TCP connection reset by peer” error. What’s next? Here are some troubleshooting steps to consider:

1. Network Analysis

Begin by examining the network. Check for any potential disruptions, high latency, or packet loss. Consider running network diagnostics tools to identify and rectify any network issues.

2. Retry the Request

In many cases, this error is transient and can be resolved by simply retrying the request. Ensure your code has proper error-handling mechanisms in place to gracefully handle such situations.

3. Optimize Server Resources

If the error is consistently occurring due to server overload, consider optimizing your server’s resources. This may involve upgrading hardware, load balancing, or optimizing resource-intensive operations.

4. Review Firewall Rules

Review the firewall and security settings on your server. Ensure that your requests comply with the server’s security policies. Make necessary adjustments to your request headers and parameters.

Best Practices to Prevent Curl 35 TCP Connection Reset by Peer

Prevention is always better than cure. To minimize the chances of encountering this error, consider the following best practices:

1. Maintain a Stable Network

Ensure that your network connection is stable and reliable. High-speed, low-latency networks are less likely to experience connection resets.

2. Optimize Server Performance

Regularly monitor and optimize your server’s performance. Implement load balancing and caching strategies to distribute the load evenly.

3. Configure Firewall Rules Carefully

Take the time to configure your server’s firewall rules meticulously. Be mindful of which requests are allowed and which are blocked.

4. Implement Robust Error Handling

Always implement robust error-handling mechanisms in your code. This ensures that even if a connection reset occurs, your application can gracefully recover.


In the world of web development, the “curl 35 TCP connection reset by peer” error is an obstacle that can be overcome with the right knowledge and strategies. By understanding the causes, troubleshooting effectively, and implementing preventive measures, developers can ensure smooth and uninterrupted data transfer. Remember, a well-prepared developer is the one who can navigate these challenges with ease and expertise. So, equip yourself with the knowledge provided in this article, and conquer the “curl 35 TCP connection reset by peer” error like a pro.