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InfraStruXure Manager Fails to Discover Rack Mount PDU's


On certain occasions, ISX Manager can fail to discover Metered and Switched Rack PDU's connected to the ISX Manager for monitoring and management.

This applies to the following Rack PDU sku #s:

AP7900 AP7930 AP7953 AP7802 AP7832 AP7862
AP7901 AP7930J AP7960 AP7802J AP7832J AP7862J
AP7901J AP7931 AP7960J AP7810 AP7840 AP7863
AP7902 AP7932 AP7961 AP7811 AP7841 AP7864
AP7902J AP7932J AP7971 AP7820 AP7850 AP7871
AP7910 AP7940 AP7990 AP7821 AP7851 AP7892
AP7911 AP7941 AP7991 AP7822 AP7852 AP7893
AP7920 AP7950 AP7800 AP7830 AP7853 AP7894
AP7921 AP7951 AP7801 AP7830J AP7860
AP7922 AP7952 AP7801J AP7831 AP7861

Upon powering the Rack PDU it will make four DHCP requests to ISX Manager for an IP address, and after the fourth non response it will transition into a timeout state and not make any further DHCP requests. This could happen if the Rack PDU was powered up before the ISX Manager or a network cable was not attached immediately to the Rack PDU or ISX Manager hub.

It was determined that failed discovery was specific to any Rack PDU with a Firmware version below 2.6.x.

There are three methods for resolving the failed discovery of Rack PDU's by ISX Manager.

Method 1
During the initial start-up ensure that ISX Manager is powered first and a network cable is connected before any Rack PDU is energized. In this configuration, as soon as the Rack PDU is powered, ISX Manager will receive the DHCP request and assign an IP address.

Note: Once the Rack PDU is discovered by ISX Manager, ensure the latest firmware is installed on the Rack PDU. Launch the ISX Manager interface and ensure that the update was successful by double clicking on the Rack PDU in the device list and navigating to the ""Help"" and ""About System"" tab.

Method 2

By depressing the reset switch on the front of the Rack PDU, a reboot will occur and reinitialize the DHCP request process. Once the DHCP process is reinitialized ISX Manager will successfully discover each connected Rack PDU.

Method 3
Connect to the Rack PDU through a serial interface. Using a RS-232 to RJ-11 serial cable (APC Part # 940-0144) connect the RS-232 end to your computer and RJ-11 end to the RJ-11 port on the Rack PDU. Once connected open a HyperTerminal session with the following settings: (9600, 8, None, 1, None)

Next hit enter and log into the Rack PDU using the default username and password of apc and apc (both in lower case). From the control console select ""System"", then ""Tools"", and then ""Reboot"".

Note: This will not cause any of the switched outlets to reboot. This only resets the network interface.

If the Rack PDU is still not discovered than please verify the following:

1) If the Rack PDU has any configured SNMP community string names on the Access Control section under Network/SNMP then make sure that they are listed under the SNMP tab of the “System Management/Device Access” menu on the ISX Manager

2) If the Rack PDU has any configured IP addresses populated in the ""NMS IP/Domain Name"" field then this will restrict SNMP traffic to the RM PDU. If this is the case then there are several possibilities on how to allow for the ISX Manager to have access. The first option would be to use the third and fourth lines in the Access Control section, which are not used by default. If all fields are populated then wildcards can be used to allow for additional access. For example an IP of will only allow that IP to access the RM PDU using SNMP but will allow any device on the .1 segment to be able to access the device using
SNMP. Edit this field using wildcards so that the ISX Manager or ISX Manager's segment has access to the RM PDU. An IP of or will not restrict any SNMP traffic based on the requesting IP.

3) The User Name and Password for the Rack PDU are listed under the Administrator Accounts tab of the “System Management/Device Access” menu

4) Verify that the following network ports are not being blocked: 161,162, 6000,9950.

Note : ISX Manager version 4.6.1 includes a ""Discovery Results"" feature that will assist in troubleshooting nodes that fail to add.

If the Rack PDU has still not been discovered, than please contact APC Technical Support.

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