A Simple Guide to Proxy Error and Troubleshooting Issues

Proxy server errors are sometimes an issue when scraping, especially if you’re new to it. Diagnosing and troubleshooting these errors can be challenging due to a variety of status codes, each with a unique meaning and solution. However, by understanding these codes, you can easily handle proxy server IPs and complete your scraping tasks with ease. This article is an explanation of common proxy server errors and the technical solutions that are available for their resolution.

What is a proxy error?

A proxy server error occurs when you’re trying to access a web page through a proxy server, but the server cannot process the query properly or answers incorrectly. That can be caused by network issues, server issues, setup errors, or unsupported functionality. The error code might require a specific solution.

HTTP response status codes are divided into five classes based on the first digit of the code, with the first two classes being informational and requiring no action. The other three classes indicate problems that require attention and additional steps.

They are;

1. 1xx — informational
2. 2xx — Success
3. 3xx — Redirection
4. 4xx — Client Error
5. 5xx — Server error

“Unable to connect to proxy server…”

There are several types of proxy error codes, such as 407 (Proxy Authentication Required), 502 (Bad Gateway), and 503 (Service Unavailable). That may indicate a problem on your proxy server or in your proxy setup. So what is the meaning of a proxy error? Common reasons for proxy issues are:

• The proxy server has failed or becomes overloaded.
• The website is blocking or disallowing the proxy server.
• The proxy needs to authenticate or authorize.
• Proxy incompatible with website’s log or encryption.
• Proxy settings are wrong or damaged.

What are the Common proxy error codes and their solutions?

1xx Informational Error Code

These are preliminary answers that are seldom needed. When the server processes the requests, these requests are considered used;

100 — Continue

The HTTP status code 100 (Continue) is used by a server to indicate to a client that the server has received part of the request, and the client can proceed with sending the rest of the request. The typical use of this status code is when the client sends a request header that includes the statement “Expect: 100-continue”. After receiving this header, the server replies with a status code of 100, which signals the client to send the body of the request. If the server rejects the initial request header, the “Expect” header is used to prevent further requests from being sent.

101 — Switching Protocols

If the client requests to switch the communication protocol during a browser transaction, the Web server responds with a status code of “101”. A “100” HTTP status code is returned to acknowledge the successful change.

102 — Processing (WebDAV)

In certain cases, when a client sends a complex WebDAV request with multiple sub-requests, the web server may require a significant amount of time to process it. That delay can lead to timeout errors on the client side. To avoid this problem, the server sends a status code called “102 — Processing” to inform the client that it has received the request and is currently processing it. The purpose of this status code is to prevent client-side timeouts and provide the client with the assurance that the request has been received and is being processed.

103 — Early Hints

When a web server sends an HTTP status to a browser, it can also send an early hint to the client’s browser using code “103 — Early Hints”. That indicates to the browser that the server has not yet started processing the HTTP requests.

2xx Successful Status Code

If you see an HTTP status code between 200 and 299, it means that the server received and processed your request successfully. The most common code you’ll receive is 200, which means that the server has fulfilled your request. Any other 2xx code besides 200 OK could indicate an error, so it’s essential to pay attention to these codes to ensure that the request was processed correctly.

Here are the most common 2xx status codes;

201 — Created

If you see this status code, it means the server has finished processing your request and created a new resource. That means that the server has taken the information you provided and used it to create a new response. For example, this could happen when you log in to a website and the server creates a new response based on your login information.

202 — Accepted

When a client sends a request to the server, the server receives it and indicates that it has been received with “202 — Accepted”. However, the request has not yet been processed at this point. The server will process the request later, and only then will it be possible to know the outcome of the processing.

203 — Non-Authoritative Information

When a server processes a request and returns information from another resource to the client, it may send a code called “203 — Non-Authoritative Information”. The code indicates that the request was successfully processed but the information received came from a different source.

204 — No Content

When a request is received by the server but no content is available, it will send a response code indicating that no content is returned. That response code is “204 — No Content”.

205 — Reset Content

The server successfully processed a request but didn’t return any content, just like the 204 code. Code 205, on the other hand, indicates to the client that the document view has cleared.

206 — Partial Content

If a server is unavailable to provide the entire requested resource due to a specific range specified in the request header, it sends an error code to the client.

3xx — Redirection Error

If you see a 3xx code, it means you need to do something more to complete your request. Usually, this isn’t a problem if you’re using a browser like Google Chrome or Safari. But if you’re using a script, you’ll have to deal with these codes yourself. Scripts can be helpful because they allow you to avoid redirecting requests to other URLs. However, you must be careful. If you’re not, you could end up creating an infinite loop of redirects. Web browsers are designed to prevent this by not allowing more than five consecutive redirects of the same request.

Some of the most common 3xx error codes are as follows;

300 — Multiple Choices

If you receive a “300 — Multiple Choices” error code, it means that the URL you requested is pointing to more than one resource. To fix it, check the HTTP headers and make sure the URL is pointing to a single resource so that the user agent can access the page without any problem.

301 — Resource Moved Permanently

That error occurs when a web server permanently redirects an original URL to another URL. When a user receives a “301 — Moved Permanently” status code, they can’t see the original URL, and search engines will only index the redirected URL. If there are more than 5 redirects for a single URL, it could result in an infinite loop, and browsers like Chrome will display a “Too Many Redirects” message.

302 — Resource Moved Temporarily

“302 — Moved Temporarily” is a code for temporary redirects where the User Agent is redirected to a different URL after requesting the original URL.

303 — See Another Resource

If you receive a 303 — See Other Resource, it means that the requested resource is at a different URL address and must be requested using a “GET” method. Keep in mind that search engines will only index the originally requested page if it receives a “200 — Success” code.

304 — Resource Not Modified

A “304 — Resource Not Modified” code is sent by a server when a requested resource hasn’t changed since the last request. The server assumes that the client already has a copy of the resource. The “If-Modified-Since” or “If-Match” line will contain the time of the last modification. To speed up indexing and reduce the load on the crawler, you should use the 304 code if your web page hasn’t changed since the last time the crawler accessed it.

305 — Use proxy

The code “305 — Use Proxy” means you need a proxy server to access the resource. The response will give you the proxy server’s address. Some browsers, like Internet Explorer, won’t display this information due to security concerns.

306 — Switch Proxy

The code “306 — Switch proxy” means that the server needs to use a specific proxy for the upcoming request(s).

307 — Temporary Redirection

Code 307 is a temporary redirect status code used by the HTTP/1.1 protocol. It indicates that a requested resource has been moved to a different address temporarily, which is specified in the Location header of the request. To access the original URL, you should make the next request.

308 — Permanent Redirect

308 — Permanent Redirection code indicates permanent redirection, similar to 307 for temporary redirection, except that it doesn’t change the HTTP method.

4xx Client Error Codes

HTTP proxy errors can be separated into two types: 4xx and 5xx error codes. Getting a 4xx error means the problem is on your end. It can be your request, your browser, or an automated bot.

400 — Bad Request

This “400 — Bad Request” message means that there’s an issue with your request. It could be due to syntax errors, incorrect formatting, or misleading routing of your request. The problem might be related to your proxy server or the website you’re trying to access.

401 — Unauthorized

The error code “401 — Unauthorized” means the website you’re trying to access needs authentication. The proxy server returns this error when the webserver requires credentials. To access the resource, you need to provide the necessary authentication details.

402 — Payment Required

This 402 — Payment Required code was created for digital payment systems, but it’s rarely used and there’s no standard convention for it yet.

403 — Forbidden

When you see the number 403, it means that the server understands your request but can’t show you the content you want to see. That usually happens when you don’t have permission to look at the resource you’re trying to access.

404 — Not Found

The 404 code means that the online resource you’re trying to access is unavailable, even if the request is valid. Most of the time, this happens because the URL doesn’t exist, isn’t correct, or has been redirected.

405 — Method Not Allowed

If a server has disabled a request method, it will respond with the error code “405”. That means that the method cannot be used to access the requested resource.

406 — Not Acceptable

During server-driven content negotiation, the web server sends a response if it doesn’t find content that matches the criteria set by the user agent.

407 — Proxy Authentication Required

If you receive a 407 code from a proxy, it means that authentication is required or a tunnel connection has failed. That could be due to incorrect authentication or inaccurate credentials in your scraper. It could also be because your IPs are not whitelisted in the proxy settings. To solve this error, update your proxy settings with whitelisted IPs and proper credentials.

408 — Request Timeout

The 408 error code occurs when the server is configured to wait for a request from the client, but none is received. The client can resend the same request at any time. If this error persists, check your web server’s load and connectivity to identify possible issues.

409 — Conflict

The 409 — Conflict error occurs when a client’s request cannot be completed due to a conflict with the current state of the resources. The error is not related to standard server authority or security but to a specific application. The response body provides users with enough information to identify the conflict’s source and fix the issue.

410 — Gone

The server sends a 410 error code when the requested resource is permanently gone and won’t be available again. It’s similar to the 404 error, but it’s permanent.

411 — Length Required

The error code indicates that the server is not accepting the request due to an undefined content length. To resolve this, the client must include a valid content-length header field in the request, which is the length of the message body.

412 — Precondition Failed

When request-header fields have false preconditions, the server responds with this error code. It allows clients to set preconditions on a resource’s metadata and keeps the requested method from being applied to any other resource.

413 — Request Entity Too Large

If you send a request that’s too big, the server may stop it and disconnect you. That can happen when you try to upload large files using the HTTP PUT method. The server may have limits on how big of a file you can upload.

414 — Request-URL Too Long

A web server may reject a request if the Request-URL is too long. That may happen if a client converts a “POST” request to a “GET” request with a long query or if there is a URL redirection loop. The server may also reject the request if a client attempts to exploit security holes in the server. Most web servers have generous URL limits, but if you still get an error message with a valid long URL, the server needs to be reconfigured.

415 — Unsupported Media Type

The web server can’t fulfill the request because the requested resource doesn’t support the format of the entity for the requested method.

416 — Requested Range Not Satisfiable

Servers return a 416 status code when a request contains a Range request header field and the range-specific values don’t overlap the current scope of the selected resources. That code is returned if the request does not have an If-Range header field.

417 — Expectation Failed

When a web server receives a request with an “Expect” header field that it cannot fulfill, it will usually respond with a specific status code. The same status code may also be used by a proxy server that discovers the next-hop server is unable to fulfill the request.

429 — Too Many Requests

Sending too many requests from the same IP address within a limited time frame can cause an error due to website restrictions. To solve this issue, use rotating proxies and set delays between requests per IP and time frame.

5xx — Server Error

The server sends 5xx errors when it receives a request but can’t process it. Rotate IPs, change the proxy network and IP type, and use a residential proxy network to fix the errors.

You may receive error codes such as –

500 — Internal Server

Error code 500 indicates that the server encountered an unexpected condition and cannot respond to the request.

501 — Not Implemented

If the server cannot fulfill a request due to unsupported or unrecognized methods used in the request, it will return a “501 — Not Implemented” error.

502 — Bad Gateway

An error while collecting data may happen if the server acting as a gateway or proxy receives an invalid response from another server. If the internet connection is denied by super proxies or requests are sent, the system may detect that the IP is unavailable for the selected settings, leading bots to indicate a 502 code.

503 — Services Unavailable

The “503 — Service Unavailable” error occurs when a server is overloaded with requests or undergoing maintenance. To resolve the issue, check the status of the server that was requested, if possible.

504 — Gateway Timeout

“504 — Gateway Timeout” error message occurs when a server acting as a gateway or proxy doesn’t receive a response from the next server in the request chain. The next server is external to the first server and is taking too long to respond to the request.

505 — HTTP Version Not Supported

The server sends a “505 — HTTP Version Not Supported” code when it cannot support the HTTP protocol version used in the request message.

507 — Insufficient Space

When you see “507 — Insufficient Storage,” it means that the server doesn’t have enough disk space to handle the request. That can happen when the server is full and cannot store any more data.

510 — Extensions are Missing

The request cannot be processed by the server due to an unsupported extension. The server responds with the error code “510 — Not Extended”.

How To Fix Proxy Errors?

If you’re new to web scraping, you may encounter proxy errors. To avoid these problems, we’ve already given you some tips. In this section, we will discuss each solution in detail. You can minimize the chances of encountering these problems by following these techniques from the beginning.

Switch To Residential Proxies

Choosing the right type of proxy is important to avoid errors when scraping data. IPs from data centers are less expensive, but they may not work well for scraping because they only provide a limited pool of IPs. For example, in the case of Windows 10, there may be too many requests from a single address, which can be a source of errors.

Residential proxies are a better option when it comes to scraping data. They are real devices, and they are redirected before the request is sent to the server of interest. These proxies offer a larger pool of IP addresses, making them easier to rotate and avoid being blocked. To make sure you don’t run out of IPs when scraping, X-Byte offers a residential proxy.

Improve Your Rotation

If you make multiple requests from the same IP address, the site you’re trying to scrape may block your access. Webmasters protect their sites against both DDoS attacks and scraping. Making a lot of requests from one IP address can look like an attack and trigger anti-scraping measures that may restrict your access.

You can use a proxy management tool or a scraper that can manage IP addresses to avoid this. That will allow you to change your IP address for each request you make, making it less likely that the website will notice anything unusual. Using this method will make your scraping process a lot faster and more efficient.

Decrease The Number Of Requests

Sending too many requests to a server can cause problems. The server can become overloaded, which can lead to problems with the computer’s proxy server. Even if you rotate proxies correctly, it’s important to keep the number of requests at a reasonable level. Sending more requests in a given time frame may help you collect data faster, but it may trigger anti-DDOS and anti-scraping measures that webmasters use.

To avoid Internet proxy server errors, try adding a delay of a few seconds between requests. That won’t slow the process down significantly, but it can help you avoid getting too many errors.

Make Sure The Scraper Can Solve Blocks

You may need a better scraper if you’re having trouble scraping data and you keep getting proxy connection errors. That is especially important if you’re working with merchant sites that take a lot of steps to protect their stores from fraud. A good scraper can bypass over a hundred different restrictions, making it essential for successful and efficient data collection. Make sure you have a reliable scraper if you want to collect data quickly and successfully.

Final Thoughts

Encountering proxy status error codes can be frustrating when you’re trying to access your data. Fortunately, most of them can be easily resolved if you understand their meaning and know what steps to take. To address these errors, it’s important to first understand what they mean and then follow the basic steps for fixing them. To reduce downtime and keep your data accessible, stay informed and take proactive measures. If you ever run into any of these issues, don’t worry. Just refer back to this guide and know that X-Byte is here to help you every step of the way.

This Blog originally published here.