Chapter 4. Nortel Networks Layer 2/3 GbE Switch Module architecture 27
򐂰Spanning Tree (STP) is disabled by default for all internal ports.
Preset default values for ports going to the Management Modules (includes ports MGT1 and
MGT2):
򐂰Speed is hard-coded at 100 full and cannot be changed.
򐂰Ports MGT1 and MGT2 cannot be disabled.
– This is by design to ensure that the links to the BladeCenter Management Modules are
not inadvertently or intentionally brought down by the administrator.
– Note that only one of these ports (MGT1 or MGT2) is active at one time (only one
Management Module is active at any given time).
򐂰Both ports are hard-coded as untagged VLAN 4095 (internal management VLAN).
򐂰Nortel has implemented a hidden filter (not visible or controllable by the administrator) that
prevents any packet entering one of the uplink ports or the internal ports (INT1 -14 and
EXT1 - 6) from exiting toward the Management Module ports (MGT1 - 2) and vice-versa.
This filter is implemented to ensure isolation of the internal BladeCenter management
network.
Ports EXT1 through EXT6: Connects to external ports 1 through 6, respectively:
򐂰Preset default values for ports going to external connections (includes ports EXT1 through
EXT6): Untagged and configured on VLAN 1.
򐂰These ports default to Disabled when in a new IBMEserver BladeCenter. You must use
the Management Module Web interface, under I/O Module tasks Advanced settings, to set
External Ports to Enabled to bring them up the first time.
RS232 Console port:
򐂰Default settings:
– Baud rate: 9600
– Data bits: 8
– Parity: None
– Stop bits: 1
– Flow control: None
– Emulate: VT100
򐂰Serial Console Cable - (FRU 02R9365).
This USB-style connector enables connection to the GbE switch module.
The management VLAN IP address information is not lost during factory reset
The management VLAN IP address information is not lost as long as Preserve new IP
configuration on all resets is enabled on the Management Module.
As a direct result of a feature being enabled on the Management Module (under I/O Modules
Advanced Setup), after a Nortel GbESM is cleared (reload or through the GUI), the
BladeCenter Management Module provides its currently saved IP information for that Nortel
GbESM. This is to help ensure that the Nortel GbESM can always be accessed over from the
Management Modules. This action (providing or not providing the Nortel GbESM its default
address) can be partially controlled from the Management Modules Web interface.
See“Enabling Nortel Networks L2/3 GbESM uplink ports through the Management Module”
on page 48 for details about enabling or disabling the feature called Preserve new IP
configuration on all resets.