Basic Concepts of Wireless Packet Obtaining
What Is Wireless Packet Obtaining?
During the network maintenance, when a STA is faulty (for example, a failure to obtain an IP address), maintenance personnel need to obtain and analyze packets on the wireless side to remotely locate the fault. The wireless packet obtaining function allows users to remotely configure APs to obtain air interface packets without using third-party tools onsite. This function enables maintenance personnel effectively and conveniently to locate faults and reduces maintenance costs.
Which Types of Packets Can Be Obtained Using the Wireless Packet Obtaining Function?
The wireless packet obtaining function obtains packets only on the air interface but not wired-side packets. The types of obtained packets vary according to the AP radio working modes.
- When the AP radio works in monitor mode, all management frames and control frames on a specified channel can be obtained.
- When the AP radio works in normal mode, the control frames, management frames, and data frames sent and received by only the local AP can be obtained. To protect user privacy, only packet headers of the data frames are obtained.
How Can Obtained Wireless Packets Be Saved?
Two modes available for saving obtained wireless packet files: local cache and real-time mode.
If the AP used for wireless packet obtaining can communicate with the maintenance personnel's server, you can select the local cache mode or real-time upload mode.
In remote scenarios, if the AP used for wireless packet obtaining cannot communicate with the local server of maintenance personnel, the obtained packets can only be cached locally. Specifically, the maintenance personnel need to save the obtained packets on a remote device and then send them to the local server.
- Local cache
By default, wireless packet files are saved in local cache mode. The AP saves the obtained wireless packets locally and uploads them to the specified address through FTP, SFTP, HTTP, or HTTPS.
- Fit AP and Fat AP: The wireless packet obtaining function can be manually disabled after being enabled. During the packet obtaining process, when the size of stored files reaches the maximum local storage capacity (configurable; 1024 KB by default), the device automatically stops obtaining wireless packets and discards excess packets. Additionally, in V200R021C10 and later versions, the function automatically stops 10 minutes after being enabled, preventing resource occupation. When the AP communicates with the server, the upload process can be manually triggered to upload the obtained packet files to the specified server using FTP or SFTP.
- Cloud AP: When the wireless packet obtaining function is enabled, the duration for obtaining packets also needs to be set. In this way, the function is automatically disabled when the duration expires. During the packet obtaining process, when the size of stored files reaches 1024 KB (fixed value, unconfigurable), the device stops obtaining wireless packets. The upload process is then automatically triggered to upload the packet files to the file server of the SDN controller using HTTP or HTTPS (HTTPS is used by default in V200R021C10 for security purposes), so that users can download the packet files to a local PC.
In AC+Fit AP networking, users must manually disable the wireless packet obtaining function before uploading the obtained packet files, regardless of whether the wireless packet obtaining function automatically stops. In other networking modes, the obtained packet files can be directly uploaded after the wireless packet obtaining function automatically stops, without the need to manually disable it.
To improve transmission security, SFTP or HTTPS is recommended for uploading obtained packets to a specified address.
- Real-time upload
In real-time upload mode, the AP uploads the obtained packet files to the server with the specified address in real time through cables. In this case, the size of the obtained packet files is not limited.
Which Devices Support Wireless Packet Obtaining?
The wireless packet obtaining function is available for all AC models.
For APs running V200R021C10 or later, the wireless packet obtaining function is not supported by the AirEngine 5761-10W, AirEngine 5761-10WD, AirEngine 5761S-10W, and AirEngine X762 series, and is supported by other models in Fit, cloud, or Fat mode.
For APs running versions earlier than V200R021C10, the wireless packet obtaining function is not supported by AirEngine series (except the AirEngine 5760-10), and is supported on other models only in cloud or Fit mode.
In Fit AP scenarios, the wireless packet obtaining function can be configured on the AC using the CLI or web system. The functions configured using the two methods are the same. Obtained packet files can be saved locally or uploaded in real time. This function cannot be configured for AirEngine series APs on the web system of the AC running a version earlier than V200R021C10.
In cloud AP scenarios, the wireless packet obtaining function can be configured on the SDN controller. Currently, the obtained packet files can be only saved locally, and need to be uploaded to the file server of the SDN controller for maintenance personnel to download and check. In V200R019C00 and earlier versions, CloudCampus@AC-Campus is used as the SDN controller. In V200R019C10 and later versions, iMaster NCE-Campus is used as the SDN controller.
In Fat AP (including leader AP+Fit AP) scenarios, the wireless packet obtaining function can be configured on the Fat AP (or leader AP in leader AP+Fit AP networking) using the CLI, and the obtained packet files can be saved locally or uploaded in real time.
