Configuring SNMP v2 on Cisco Devices
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Module 1: Lab Setup & Network Diagram
1.1 Required Software & Tools
GNS3
PRTG Network Monitor (Installed on 192.168.202.10)
A simple network topology
1.2 Lab Topology
Router (R1)
f0/0
192.168.202.1/24
Switch (Sw1)
VLAN 1
192.168.202.2/24
PC1 (VPCS)
e0
192.168.202.11/24
PRTG Server (NMS)
eth1
192.168.202.10/24
The PRTG is running on 192.168.202.10 and will monitor network devices via SNMP v2.
Module 2: Basic Configure
2.1 R1 Router
2.2 Sw1 Switch
2.3 PC1
Module 3: Configure SNMP v2 on Cisco Router
Set SNMP Community String (Read-Only Access for PRTG Server 192.168.202.10):
Define a contact & location:
Enable SNMP traps to PRTG Server (192.168.202.10):
Save the configuration:
Module 4: Configure SNMP v2 on Cisco Switch
Set SNMP Community String (Read-Only Access for PRTG Server - 192.168.202.10):
Define a contact & location:
Enable SNMP traps to PRTG Server (192.168.202.10):
Save the configuration:
Module 5: Install & Configure PRTG Network Monitor (192.168.202.10)
Install PRTG on 192.168.202.10
Download PRTG Network Monitor from Paessler’s website.
Install PRTG on 192.168.202.10 (Windows Server/PC).
After installation, log in to PRTG Web Interface (
http://127.0.0.1).
Module 6: Add Cisco Devices to PRTG
6.1 Add Router to PRTG (192.168.202.1)
Go to Devices → Add Device.
Enter Router Name:
Cisco R1.Set IP Address:
192.168.202.1.
Under Credentials for SNMP Devices, enter:
SNMP Version: v2c
Community String:
public
Click Save & Continue.
5.2 Add Switch to PRTG (192.168.202.2)
Go to Devices → Add Device.
Enter Switch Name:
Cisco Sw1.Set IP Address:
192.168.202.2.
Configure SNMP with:
SNMP Version: v2c
Community String:
public
Click Save & Continue.
Module 7: Monitor Traffic & Alerts
7.1 Add SNMP Sensors
In PRTG Web Interface, select R1.
Click Add Sensor → SNMP Traffic.
Select interfaces to monitor (e.g.,
FastEthernet0/0).
Click Add Sensor.
Repeat the same steps for Sw1 and monitor VLAN 1.
Module 8: Test SNMP Communication
Open VPCS on GNS3 and test network connectivity:
Now, check the traffic of FastEthernet 0/0 of R1:
Module 9: Troubleshooting SNMP Issues
9.1 Check SNMP Status on Cisco Devices
On Router & Switch:
Check if the SNMP community is correctly set:
9.2 Fixing Common Issues
PRTG cannot discover devices?
Ensure SNMP is enabled and 192.168.202.10 is allowed as the SNMP host.
No SNMP traffic on PRTG?
Check firewall settings on PRTG Server (allow UDP port 161 & 162).
Keywords:
SNMP v2, PRTG Network Monitor, Cisco router, Cisco switch, network monitoring, SNMP configuration, network management, NMS, Simple Network Management Protocol, PRTG setup, Cisco SNMP, network performance, network security, SNMP community string, network traffic analysis, fault detection, SNMP traps, Cisco IOS, real-time monitoring, IT infrastructure, مانیتورینگ شبکه
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