What is the X-Forwarded-For header?
The X-Forwarded-For Header is a request type header and is an alternative and de-facto standard version of the Forwarded header which is used when a client connects to a web server through an HTTP proxy or load balancer for identifying the original IP address.
What is The XFF header used for?
X-Forwarded-For The X-Forwarded-For (XFF) header is a de-facto standard header for identifying the originating IP address of a client connecting to a web server through an HTTP proxy or a load balancer. When traffic is intercepted between clients and servers, server access logs contain the IP address of the proxy or load balancer only.
What is XF X Forwarded For?
X-Forwarded-For. The X-Forwarded-For (XFF) header is a de-facto standard header for identifying the originating IP address of a client connecting to a web server through an HTTP proxy or a load balancer. When traffic is intercepted between clients and servers, server access logs contain the IP address of the proxy or load balancer only.
What is an example of a Forwarded header?
An example of a Forwarded header's syntax: HAProxy defines the PROXY protocol which can communicate the originating client's IP address without using the X-Forwarded-For or Forwarded header. This protocol can be used on multiple transport protocols and does not require inspecting the inner protocol, so it is not limited to HTTP.
What is X-Forwarded host header?
The X-Forwarded-Host (XFH) header is a de-facto standard header for identifying the original host requested by the client in the Host HTTP request header.
How do you see the X-Forwarded-For a header?
To check the X-Forwarded-For in action go to Inspect Element -> Network check the request header for X-Forwarded-For like below.
How do I get rid of X-Forwarded-For header?
Go the HTTP > Configuration > X-Forwarded-For Header. To disable, select Disable from the drop-down list.
What is X-Forwarded-For header in f5?
X-Forwarded-For is a common HTTP header and may be an expected HTTP header by a receiving system. In the provided sample iRule, you can also use a custom HTTP header name instead of the common X-Forwarded-For to better identify the HTTP header that the BIG-IP system inserts.
What is my public IP address?
Here's how to find the IP address on the Android phone: Go to your phone's settings. Select “About device.” Tap on “Status.” Here you can find information about your device, including the IP address.
What are headers in HTTP requests?
An HTTP header is a field of an HTTP request or response that passes additional context and metadata about the request or response. For example, a request message can use headers to indicate it's preferred media formats, while a response can use header to indicate the media format of the returned body.
What are forwarded headers?
The Forwarded request header contains information that may be added by reverse proxy servers (load balancers, CDNs, and so on) that would otherwise be altered or lost when proxy servers are involved in the path of the request.
What is an IP country?
IP-based Geolocation is mapping of an IP address or MAC address to the real-world geographic location of an Internet-connected computing or a mobile device. Geolocation involves in mapping IP address to the country, region (city), latitude/longitude, ISP and domain name among other useful things.
How do I get an IP address?
On an Android/tablet Go to your Wifi network settings, then select the network you're connected to. You'll find your IP address along with the other network information.
What is SNAT in F5 LTM?
SNAT is also known as Secure Network Address Translation (SNAT). It is an object that maps the source customer IP address in a request to a translation address defined on the BIG-IP device.
What is true client IP header?
True-Client-IP is a solution that allows Cloudflare users to see the end user's IP address, even when the traffic to the origin is sent directly from Cloudflare.
What is HTTP profile in F5?
The HTTP profile allows the virtual server to operate in full Layer 7 (L7) inspection mode and use features such as the following: Full HTTP iRules logic. OneConnect functionality (including OneConnect transformations)
What does X-Forwarded-For mean?
X-Forwarded-For is also an email-header indicating that an email-message was forwarded from one or more other accounts (proba bly automatically).
Is X-Forwarded-For always enough?
Just logging the X-Forwarded-For field is not always enough as the last proxy IP address in a chain is not contained within the X-Forwarded-For field, it is in the actual IP header. A web server should log BOTH the request's source IP address and the X-Forwarded-For field information for completeness.
Is X-Forwarded-For a forward or reverse proxy?
X-Forwarded-For data can be used in a forward or reverse proxy scenario.
Does Zscaler have a header?
Zscaler will mask an X-Forwarded-For header with Z-Forwarded-For, before adding its own X-Forwarded-For header identifying the originating customer IP address. This prevents internal IP addresses leaking out of Zscaler Enforcement Nodes, and provides third party content providers with the true IP address of the customer.
What does the X in PHP mean?
The X- indicates that the Forwarded-For header is non-standard. I don't think there's a difference whether a language uses dashes or underscores to refer to header names.
Is header name case sensitive?
The header name itself is case insensitive. However, when you want to query a request header, programming languages are largely case sensitive about it (again, PHP is one of them).
X-Forwarded-For
The X-Forwarded-For request header is automatically added and helps you identify the IP address of a client when you use an HTTP or HTTPS load balancer. Because load balancers intercept traffic between clients and servers, your server access logs contain only the IP address of the load balancer.
X-Forwarded-Proto
The X-Forwarded-Proto request header helps you identify the protocol (HTTP or HTTPS) that a client used to connect to your load balancer. Your server access logs contain only the protocol used between the server and the load balancer; they contain no information about the protocol used between the client and the load balancer.
X-Forwarded-Port
The X-Forwarded-Port request header helps you identify the destination port that the client used to connect to the load balancer.
Overview
The X-Forwarded-For (XFF) HTTP header field is a common method for identifying the originating IP address of a client connecting to a web server through an HTTP proxy or load balancer.
The X-Forwarded-For HTTP request header was introduced by the Squid caching proxy server's developers.
Format
The general format of the field is:
where the value is a comma+space separated list of IP addresses, the left-most being the original client, and each successive proxy that passed the request adding the IP address where it received the request from. In this example, the request passed through proxy1, proxy2, and then proxy3 (not shown in the header). proxy3 appears as remote address of the request.
Proxy servers and caching engines
The X-Forwarded-For field is supported by most proxy servers.
X-Forwarded-For logging is supported by many web servers including Apache. IIS can also use a HTTP Module for this filtering.
Zscaler will mask an X-Forwarded-For header with Z-Forwarded-For, before adding its own X-Forwarded-For header identifying the originating customer IP address. This prevents internal IP …
Alternatives and variations
RFC 7239 standardized a Forwarded HTTP header with similar purpose but more features compared to the X-Forwarded-For HTTP header. An example of a Forwarded header's syntax:
HAProxy defines the PROXY protocol which can communicate the originating client's IP address without using the X-Forwarded-For or Forwarded header. This protocol can be used on multiple transport protocols and does not require inspecting the inner protocol, so it is not limited to HTTP.
See also
• Internet privacy
• List of proxy software
• X-Originating-IP for SMTP equivalent
• List of HTTP header fields
External links
• Apache mod_extract_forwarded