portal timer offline-detect

Function

The portal timer offline-detect command sets the Portal user offline detection interval.

The undo portal timer offline-detect command restores the default Portal user offline detection interval.

By default, the Portal user offline detection interval is 300 seconds.

Format

portal timer offline-detect time-length

undo portal timer offline-detect

Parameters

Parameter	Description	Value
time-length	Specifies the Portal user offline detection interval.	The value is 0 or an integer that ranges from 30 to 7200, in seconds. The default value is 300. The value 0 indicates that offline detection is not performed.

Views

System view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

If a Portal user goes offline due to power failure or network interruption, the device and Portal server may still store the user information, which causes incorrect accounting. Additionally, a limit number of users can access the device. If a user goes offline improperly but the device still stores user information, other users cannot access the network.

After the Portal user offline detection interval is set, if the user does not respond within the interval, the device considers the Portal user offline. The device and Portal server then delete the user information and release resources to ensure an efficient resource use.

Precautions

The portal timer offline-detect command only applies to Layer 2 Portal authentication.

The heartbeat detection function of the authentication server can be used to ensure the normal online status of PC users for whom Layer 3 Portal authentication is used. If the authentication server detects that a user goes offline, it instructs the device to disconnect the user.

If the number of offline detection packets (ARP packets) exceeds the default CAR value, the detection fails and the users are logged out. (The display cpu-defend statistics command can be run to check whether ARP request and response packets are lost.) To resolve the problem, the following methods are recommended:

Increase the detection interval based on the number of users. The default detection interval is recommended when there are less than 8000 users; the detection interval should be no less than 600 seconds when there are more than 8000 users.
Deploy the port attack defense function on the access device and limit the rate of packets sent to the CPU.

Example

# Set the Portal user offline detection interval to 400s.

<HUAWEI> system-view
[HUAWEI] portal timer offline-detect 400