The Best Tech Tips

Complete list of HTTP status codes.

Through HTTP status codes, machines point out if HTTP requests were completed or not and why. Understanding the status codes’ meaning can save you time and effort while trying to fix a failure.

Complete list of HTTP status codes.

There are five categories of HTTP status codes: Server error, client error, redirection, successful, and informational.

5xx server error

500 Internal server error. The server found a condition that prevented it from fulfilling the request.

501 Not implemented. The server can’t handle the request because it doesn’t support the required functionality.

502 Bad gateway.

503 Service unavailable.

504 Gateway timeout.

505 HTTP version not supported.

506 Variant also negotiates. Internal setting up error on the server.

507 Insufficient storage.

508 Loop detected.

509 Bandwidth limit exceeded (Apache).

510 Not extended.

511 Network authentication required.

598 Network read timeout error required.

4xx Client error

400 Bad request. The server didn’t understand the request because of the invalid syntax on it.

401 Unauthorized. The request demands the authentication of the user.

402 Payment required.

403 Forbidden. The request is legal, but the server refused to fulfill it. Authentication here won’t make a difference.

404 Not found.

405 Method not allowed.

406 Not acceptable.

407 Proxy authentication required.

408 Request timeout.

409 Conflict. 

410 Gone. The resource requested is not available at the server anymore, and there’s no known forward address.

411 Length required.

412 Precondition failed.

413 Payload too large.

414 URI too long.

415 Unsupported media type.

416 Range not satisfiable.

417 Expectation failed.

418 I’m a teapot.

421 Misdirected request.

422 Unprocessable entity.

423 Locked.

424 Failed dependency.

425 Too early.

426 Upgrade required.

428 Precondition required.

429 Too many requests.

431 Request header fields too large.

450 Blocked by Windows Parental Controls (Microsoft).

451 Unavailable for legal reasons.

3xx redirection.

300 Multiple choices.

301 Moved permanently. The resource requested was changed permanently to a different URL.

302 Found. The resource requested was changed to another URL temporarily.

303 See other. The request’s response can be found on a different URL that should be recovered through a GET method.

304 Not modified.

305 Use proxy.

306 Switch proxy.

307 Temporary redirect.

308 Permanent Redirect (experimental).

Web redirect record: How to use it?

2xx successful

200 Ok. It states the success of the request.

201 Created. The request was fulfilled, so a new resource was created.

202 Accepted. The request was accepted to be processed, but its process is not completed yet. 

203 Non-authoritative information.

204 No content.

205 Reset content.

206 Partial content.

207 Multi-status.

208 Already reported.

226 IM used.

1xx informational

100 Continue. The server received the first part of the request. 

101 Switching protocols.

102 Processing. The server accepted the full request, but it’s not fully completed yet.

103 Early hints. It allows the user agent the pre-loading of resources while the server gets a response ready.

Suggested article: Most frequently used DNS commands.


Next time you get an HTTP status code, pay attention to it! It’s the clue you need to fix the cause of an issue without delay.

Six Benefits Of IPv6

What is IPv6?

IPv6 is the latest version of the Internet protocol (IP). The purpose of Internet protocols is to set specific rules for the devices to send and receive information successfully. The exchange of information is between two hosts. So, for that reason, they have to be able to be identified. IP addresses come to help in this situation to track each host’s location. Finally, the two corresponding IP addresses are acknowledged, and the route is established for the entire data exchange.

An interesting fact is that IPv6 was officially introduced in 1995. That is more than twenty years! The massive growth of devices and the Internet’s gained popularity forced the need for the new IPv6. It was decided that IPv4 could not be able to provide the required amount of IP addresses. So, that is why IPv6 got developed. However, the transition to the newer version takes time. The majority of the devices, such as computers, smartphones, and the Internet of things (IoT), request a unique IP address to connect to the web daily. Let’s talk a little bit more about the benefits of IPv6!

Effective routing

With IPv6, the size of routing tables is reduced, and routing is a lot more effective. It lets ISPs aggregate the prefixes of their clients’ networks into an individual prefix and state this one prefix to the IPv6 Internet. Furthermore, in IPv6 networks, the fragmentation is managed by the source device and not by the router. That is possible by applying a protocol to identify the path’s maximum transmission unit (MTU).

Effective packet processing

The IPv6 has a more simple packet header that produces more efficient packet processing. Furthermore, in contrast with IPv4, IPv6 doesn’t include IP-level checksum, and the checksum is not recalculated at each router hop. Most link-layer technologies already have checksum and error-control abilities, because of that, eliminating the IP-level checksum was possible. Besides, the majority of transport layers that control end-to-end connectivity also hold checksum that lets error detection.

Directed data flow

The new IPv6 supports multicast, which allows bandwidth-intensive packet flows. They can be carried to various destinations simultaneously and save network bandwidth. Hosts that are not interested will no longer process broadcast packets. Moreover, the IPv6 header has a new field. It is called Flow Label, and it can recognize packets that belong to the related flow.

Simple network arrangement

IPv6 comes with a built-in auto-configuration for address assignment.

A router is going to send the prefix of the local link in its router advertisements. Therefore, a host can produce its personal IP address via adding its link-layer (MAC) address, transformed in Extended Universal Identifier (EUI) 64-bit arrangement, to the 64 bits of the local link prefix.

New services support

Actual end-to-end connectivity at the IP layer is reconstructed by excluding Network Address Translation (NAT). Additionally were enabled brand-new and helpful services. As a result, peer-to-peer networks are much easier to make and sustain, plus services like VoIP and Quality of Service (QoS) are getting more robust.


IPv6 has a boost with IPSec. It offers authentication, confidentiality, and data integrity. However, IPv4 ICMP packets have the potential to transfer malware, so usually, they are blocked by corporate firewalls. Yet, the firewalls may permit ICMPv6, which is the new appliance of the Internet Control Message Protocol for IPv6. The reason is IPSec is possible to be used to the packets of ICMPv6.