HP Network Direr Software Products manual Discovery Report Errors and Warnings

Discovery Report Errors and Warnings 149

The following devices have support for the Spanning Tree Protocol enabled. Links connected to these devices may in the future be blocked by the Spanning Tree Protocol. 3Com Network Director may not be able to detect this occurring.

Some third party devices do not provide suitable MIB support to allow 3Com Network Director to initially determine and subsequently track changes in spanning tree topology, or provide a non-standard implementation. As a result, the topology that 3Com Network Director depicts may not be accurate.

A device has been seen (or "learned") on multiple ports of another device. This implies there is a loop in the network. 3Com Network Director may not represent the topology of the network accurately.

Changes in network topology, such as a wireless device moving from one wireless access point to another, or changes in spanning tree topology, may result in a device being seen to move ports on another device. If this occurs during Network Discovery then 3Com Network Director may not be able to depict the topology of the network accurately.

It is usually possible to address this issue by rediscovering the subnet or subnets of the devices in question.

The following devices have a device performing ARP proxies for them.

If you have a 3Com SuperStack 3 Firewall in your network that is operating in transparent mode then any ARP requests sent to devices on the other side of the firewall will be handled by the firewall itself and it will respond with the MAC address of the firewall. In addition the firewall will substitute its MAC address as the source address in any packets it receives that are destined for an IP address on the other side of the firewall. This technique is known as ARP proxy.

3Com Network Director is unable to determine the MAC addresses of devices on the other side of a 3Com SuperStack 3 Firewall, but is able to identify the IP addresses of such devices. As a result, 3Com Network Director may not be able to depict the topology of the network accurately.

3Com Network Director could not determine a speed for at least one interface on the following devices.