HP BladeSystem Onboard Administrator cabling

HP BladeSystem 77536 HP BladeSystem Onboard Administrator cabling





Enclosure link-down port

Connects to the enclosure link-up port on the enclosure beneath it using a CAT5 patch cable.


Enclosure link-up port and service port

Connects to the enclosure link-down port on the enclosure above it using CAT5 patch cable. On a stand-alone enclosure or the top enclosure in a series of linked enclosures, the top enclosure link-up port may function as a service port.



Onboard Administrator Ethernet connection. Use a CAT5 patch cable to connect to the management network. Connect to this port to remotely communicate with the Onboard Administrator, all iLO ports on each server blade, and supporting interconnect module management parts.



Reserved for future Onboard Administrator connections.

If the Onboard Administrator management Ethernet port is connected to a management LAN that also connects to server ports, be sure that the server applications do not overload the Onboard Administrator management port with broadcast packets. The Onboard Administrator management port forwards all broadcast packets from the management network to all the devices inside the enclosure, and the Onboard Administrator records network packet flooding messages to the active Onboard Administrator syslog when it detects a high rate of packets. If the server connections are 1GB, and the Onboard Administrator connection is 100 MB, the server broadcast packets can easily overwhelm the port on the network switch connected to the Onboard Administrator. If the network packet flooding persists, the Onboard Administrator performance is impacted with a possibility of Onboard Administrator restart if the packet flooding overwhelms the Onboard Administrator capacity. This condition occurs is because Onboard Administrator must inspect all packets from the network it is connected to so the Onboard Administrator can act as the management conduit for internal enclosure devices, such as iLOs or Virtual Connect management interfaces. While an Onboard Administrator restart does not cause direct customer traffic outage, this action can cause unnecessary inconvenience, especially in configurations with Virtual Connect.

If the Onboard Administrator is connected to a network with a DHCP server when you power up the enclosure, the Onboard Administrator and each iLO (one for each server blade) consumes a DHCP lease.

HP BladeSystem Onboard Administrator cabling