Assigning an IP Address to an APC Network Management Card Without Software

Introduction

This guide details how to assign an IP address to an APC Network Management Card (NMC) when the proprietary APC software is unavailable. This method utilizes command-line tools like ARP and Ping.

The scenario involves managing APC SmartUPS units, specifically addressing the need to configure an NMC that has not received a DHCP lease.

The Problem

An APC Network Management Card (NMC) often requires specific software for initial configuration, including obtaining an IP address via DHCP. Without this software, the NMC may not be accessible on the network, even if physically connected.

The Solution: Using ARP and Ping

The Address Resolution Protocol (ARP) can be leveraged to establish a network connection with the NMC. This involves manually associating the NMC's MAC address with a desired IP address on the local subnet. Subsequently, a Ping command with a specific packet size is used to finalize the IP address assignment.

Prerequisites

• A computer on the same network subnet as the NMC.
• The MAC address of the APC Network Management Card. This is typically found on a sticker on the NMC itself or on accompanying documentation.

Steps to Assign IP Address

1. Locate the MAC Address: The MAC address is crucial. It can be found on the quality assurance slip that shipped with the NMC, or on a white sticker affixed to the NMC itself. In some cases, this sticker may be on the circuit board, requiring careful access to the NMC.
2. Access Command Prompt: Open a command prompt or terminal on your computer.
3. Create an ARP Entry: Use the arp -s command to associate the NMC's MAC address with a chosen IP address. The format is:

   arp -s [IP_ADDRESS_FOR_THE_NMC] [MAC_ADDRESS_OF_THE_NMC]

   Replace [IP_ADDRESS_FOR_THE_NMC] with the desired static IP address for the NMC and [MAC_ADDRESS_OF_THE_NMC] with the actual MAC address (e.g., 00-11-22-AA-BB-CC).

4. Send a Ping Packet: Use the ping command with a specific packet size to trigger the NMC to adopt the IP address defined in the ARP entry.
   • For Windows: ping [IP_ADDRESS_ASSIGNED_ABOVE] -l 113
   • For Linux/macOS: ping [IP_ADDRESS_ASSIGNED_ABOVE] -s 113

   Replace [IP_ADDRESS_ASSIGNED_ABOVE] with the IP address you assigned in the previous step.

5. Telnet to the NMC: Once the IP address is assigned, you can access the NMC via Telnet.

   telnet [IP_ADDRESS_OF_THE_NMC]

   Use the default username and password: apc for both.
6. Configure and Save: Within the Telnet session, configure any necessary settings and ensure to log out to save the changes.

After these steps, the NMC should be accessible via its web interface for further configuration and monitoring.

Important Considerations

Caution: While it is possible to physically remove the NMC from a running UPS unit, this is strongly discouraged due to safety risks. If necessary, proceed with extreme caution.

Best Practice: It is highly recommended to document all network device configurations, including MAC addresses and assigned IP addresses, to avoid future troubleshooting complexities.

Visual Aid Description

An image displays the back of an APC Network Management Card (model AP9619). It shows the card itself with various electronic components and connectors. A prominent white sticker is visible, containing printed information including the MAC address, which is essential for the configuration process described in this guide.