Introduction

SNMP (Simple Network Management Protocol) is a network management standard protocol based on the TCP/IP protocol stack, adopting the Client-Server architecture model. This protocol provides a standardized device monitoring and management interface through the Management Information Base (MIB).

Core Functional Features

• Device Status Monitoring: Real-time acquisition of network device operating parameters
• Performance Data Acquisition: Collect metrics such as bandwidth utilization, CPU load, and memory usage
• Configuration Management: Remotely modify device configuration parameters
• Fault Alarm: Actively Push Abnormal Event Notifications

Version	Security Features	Authentication Mechanism	Encryption Support	Applicable Scenarios
SNMPv1	Foundation	Community string	None	Intranet Monitoring
SNMPv2c	Enhanced	Community string	None	General Application
SNMPv3	Advanced	User Authentication	Support	environment with high security requirements

Configuration steps

Basic Service Configuration

Service Enablement Settings:

1. Check the "Enable SNMP service" checkbox
2. Confirm that the service status is displayed as enabled

Network Parameter Configuration:

• IP Version: Select "IPv4 and IPv6" (Supports Dual Protocol Stack)
• SNMP Port: The default value "161" can be retained
• VRF: Keep the default value "None"
• SNMP Version: Select "SNMPv1 and SNMPv2c" or "SNMPv1 and SNMPv2c and SNMPv3" or "only SNMPv3"

Access Control Configuration

SNMPv1/SNMPv2c Configuration

Click on the "SNMPv1/SNMPv2c" tab to perform the following configuration:

Read-only access settings:

• Read community (read-only community name):

  • Change the default value "public" to a secure string

• Read community source (read-only access source):

  • Default is "any (default)" (allows access from any IP)
  • can be modified to the SNMP server IP Address

Read/Write Access Settings:

• Write community (Read/Write Community Name):

  • Change the default value "private" to a secure string

• Write community source (Read/Write Access Source):

  • The default is "localhost" (accessible only from the local machine)
  • can be modified to the management station IP address

SNMPv3

If you need a higher level of security, click the "SNMPv3" tab:

User Authentication Settings:

• Auth User Name (Authenticated User Name): Enter User Name

  • Example: writeuser or admin

• Auth Level (Authentication Level): Select "authPriv" (Recommended)

• Allow write: Check as needed

Security Algorithm Configuration:

• Auth Algorithm (Authentication Algorithm): Select "SHA"
• Auth Password (Authentication Password): Set a strong password with more than 8 characters
• Crypto Algorithm (Encryption Algorithm): You can choose "AES" or "DES"
• Crypto Password (Encrypted Password): Set a strong password with more than 8 characters

Alarm Configuration

SNMP Traps Settings

Click on the "Traps" tab to configure alarms:

Basic Settings:

1. Check "Enable SNMP Traps" to enable the alarm function

2. SNMP Trap Server: Enter the IP Address of the server that receives alerts

   • Example: 192.168.1.50 (Monitoring Server Address)

3. SNMP Trap Port: Keep the default value "162"

4. SNMP Traps Version: Select "SNMPv2c" or "SNMPv3"

5. SNMP Trap Community: Modify the default community name

   • Change "public" to a secure string
   • Example: company_trap_2024

Alarm Event Description:

The system will automatically send the following event alarms:

• Device Startup/Restart Notification
• Network Interface Status Change
• Authentication Failure Event
• System Abnormality Alarm

Log Configuration

Log Recording Settings

Click on the "Logging" tab:

Log Function Enabled:

1. Check "Enable logging" to enable logging

2. Logging Level: Select the logging level

   • LOG_ERR: Only log error messages (recommended for daily use)
   • LOG_DEBUG: Records detailed debugging information (used for troubleshooting)

Operation Example

Taking connecting to LibreNMS as an example for demonstration:

ENOS system uses SNMPv2c

Add a device to the server

Fill in the IP address and community

System prompts that the device has been successfully added

The system can directly monitor the device status