1. Fiddler capture principle
When the fiddler software is opened, the proxy of the browser will be automatically set, and the proxy will be automatically restored when it is closed.
1. When fiddler is not enabled, you can see that the remote IP address is the Baidu server address when you visit Baidu:
2. Check that the local agent is also closed:
3. After fiddler is turned on, the access to Baidu becomes a local proxy, which is monitored by fiddler. The data packet first passes through fiddler, and then forwarded to the target server by fiddler;
4. The local proxy settings are also automatically set to open:
Two, the role of Fiddler
- View data flow between client and server;
- Capture and modify data packets;
- "Play back" the captured response packet.
Three, Fiddler interface introduction
Fourth, Fiddler captures data
1. Capture native PC data
2. Capture phone data
① Enable remote connection:
a. Select Tools–>Options... in the menu bar, select the Connection option;
b. Check Allow remote computers to connect, pop up a warning point to confirm, and restart Fiddler.
② Set up the mobile phone LAN proxy
a. Enter the mobile phone wireless network settings, click Configure HTTP proxy;
b. Select manual configuration, enter the ip address of the PC where Fiddler is located and the listening port 8888,
and click OK. data
3. Capturing local data
The capture passes through the local virtual interface (the interface address is usually the local address localhost or the loopback address 127.0.0.1), and sometimes it may not be possible to capture local data using Fiddler.
①Access using the host name If
the host name is test, access it through http://test.
②Use the Fiddler format address to access
http://ip.fiddler:port
4. Turn on proxy authentication
Enable proxy authentication and require the client to install a certificate. All requests that do not submit the Proxy-Authorization request header will return an HTTP/407 response, which is used to test the HTTP client and ensure that these rules run on the client server with the certificate.
①Open Rules–>Require Proxy Authentication
② To access the webpage, you need to enter the user name and password, both of which are 1 by default.
5. Troubleshooting
If the packets cannot be captured, check the local listening port or firewall configuration.