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Cisco Systems IntelligentGigabit Ethernet Switch Modules for the IBM BladeCenter, Software Configuration Guide
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Chapter3 Assigning the Switch IP Address and Default Gateway
Assigning Switch Information
Manually Assigning IP InformationYou can configure multiple IP addresses for a switch. Each IP address and its subnet mask must be
unique and belong to different subnets. You cannot configure IP addresses that cross other subnets on
the switch. Each IP address must be assigned to a different VLAN interface. The switch can be managed
from any valid IP address.
Because the switch is inside the IBM BladeCenter Chassis, you need to consider some special
circumstances before assigning IP addresses. The chassis management module acts as the IP proxy for
the switch if the IP address of the switch and the primary VLAN interface is in the same subnet as the
chassis management module. The chassis management module then carries the switch mana gement
traffic (SNMP, HTML, FTP, Telnet).
Because there can be multiple VLAN interfaces on a switch at a given time, you need to designate one
VLAN interface as the primary VLAN interface. The primary VLAN interface is known as the
management VLAN. The management VLANs configuration has the keyword management associated
with it. Only one VLAN interface can be configured as the management VLAN at a given time.
The management VLAN has special behaviors on the switch. The management VLAN communicates
with the chassis management module. The management VLAN is always the native VLAN on the
Ethernet interfaces that directly connect to the chassis management module. When the chassis
management module assigns an IP address to the switch, the switch applies it to the mana gement VLAN.
When the switch receives an IP address update request from the chassis managem ent module, the switch
overwrites any IP address that is configured on the management VLAN interface. The VLAN inter face
configured as the management VLAN cannot be placed int o the shutdown state.
If the switch is managed with a single IP address, we highly recommend that the chassis management
module assign the IP address to the switch. The switch IP address is configured on the chassis
management module web page. If the switch is managed by multiple IP addresses, we still recommend
that the chassis management module assign the IP address to the switch for the management VLAN. Any
additional IP addresses that you may want must be configured from the CLI.
Changing the management VLAN does not require modifying the configured IP address even if the IP
address is assigned by the chassis management module. The IP address of the current management
VLAN is automatically copied by the switch when the new VLAN interface is created and designated
as the management VLAN. To change the management VLAN, create an additional VLAN interface,
and then enter the management command on that VLAN interface. The switch automatically copies the
IP address.
Assign additional IP addresses that are needed for switch management to VLAN interfaces ot her than
the management VLAN interface.
Note The IP addresses that are assigned to multiple VLAN int erfaces must be in different subnets. The switch
does not allow two or more VLAN interfaces to have IP addresses in the same subnet.
Beginning in privileged EXEC mode, follow these steps to manually assign IP information to a VLAN
interface and then to designate that VLAN interface as the management VLAN:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface vlan vlan-id Enter interface configuration mode, and enter the VLAN to which the IP
information is assigned. The range is 1 to 4094.
Step3 ip address ip-address subnet-mask Enter the IP address and subnet mask.