【Typical Case】Troubleshooting IP Address Acquisition and Management Failures on an S2915 Switch

Keywords:

DHCP, IPAddress Acquisition Failure, Login Failure
1. Issue Description
When connected to an uplink device, the RG-S2915-24GT4MS-P-L switch fails to automatically acquire an IP address. Additionally, a PC cannot access the switch's web management interface using the default management IP address.
2. Device Model and Firmware

Device Type	Device Model	Firmware Version
Ruijie  switch	RG-S2915-24GT4MS-P-L	RGOS  11.4(1)B82

1. The switch fails to acquire an IP address automatically.
The MAC address of the switch can be viewed onthe uplink device, which acts as the DHCP server, indicating normal operation of the switch port, cable connection, and ARP process. It is suspected that either the switch configurations are incorrect or the uplink device is unable to properly execute the DHCP process.


2. Logging in to the switch using the default management IP address failed.
The user is unable to log in to the switch'sweb management interface using the default management IP address, indicating a possible change in the port's IP address. Since this switch does not have an external Reset button, managing it requires logging in through the console port. The user is advised to connect a PC to the switch using a console cable.
3. Logging in still failed after connecting the PC to the switch's console port.
The user still cannot log in to the switch'sweb management interface after connecting the console cable.


This type of USB-to-RJ45 cable requires adedicated driver. After downloading and installing the driver, and restarting the PC, the user can log in to the switch via Secure CRT.
4. Root Cause

After logging into the switch, the user discovered that the switch was not using the default configurations. Specifically, the port IP address is a static IP address, preventing access to the switch’s web management interface through aweb browser using the default management IP address. Additionally, the switch cannot acquire an IP address automatically.


5. Solution
Theoriginal plan was to run the ip address dhcp command to modify theconfiguration of the corresponding port.
Ruijie(config#)interface gigabitethernet 0/1(example)

Ruijie(config-if-GigabitEthernet 0/1) ipaddress dhcp

However,the customer requires a system reset.
Delete flash:/ config.text

Reload

After the system reset, the switch was restored to the default configuration. The switch port successfully acquires an IP address, enabling normal internet communication. Next, CWMP configuration is complete, and the device is onboarded to the cloud.