Dell PowerEdge VRTX - Manual (Page 101)

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FILE LOCATION: C:\Users\gina\Desktop\Checkout_new\Dell Plasma\User
Guide\Plasma_UGSystemConfig.fm
D E L L CO N F I D E N T I A L – P R E L I MI N A RY 4/ 1 8 /1 3 - F O R PR O O F O N LY
• DHCP Assignment
When the interface is configured as a DHCP client, it requests an IP
address from the DHCP server, until it receives one. It then sends Address
Resolution Protocol (ARP) packets to confirm the uniqueness of the IP
address. If the ARP response shows that the IP address is in use, the switch
sends a DHCPDECLINE message to the DHCP server, and sends another
DHCPDISCOVER packet that restarts the process.
Only the OOB interface IP address can be configured in the IPv4 Interface
Parameters pages.
When an IP address is assigned, it is checked for uniqueness in the following
way:
• A gratuitous ARP request is sent three times every three seconds.
• If after (3+1)*3 = 12 seconds the switch has not received the ARP
response, the IP address is considered to be unique.
• During the procedure the switch has to reply to gratuitous ARP and probe
ARP requests with the validated IP address.
The IP address is assigned even if the above validation procedure concludes
that the IP address in question is not unique, but a SYSLOG message is
generated.
In addition to the above validation procedure every time a switch receives an
ARP request with a sender IP address that is equal to its IP address defined on
the input interface it sends a SYSLOG message informing of IP duplication,
containing the sender IP and MAC addresses, from the received ARP
message.
To assign an IP address to the OOB interface, and to define subnets to which
traffic can be routed:
1 Click System > IP Addressing > IPv4 Interface Parameters in the tree
view to display the IP Interface Parameters: Summary page.
The previously-assigned IP addresses are displayed.
2 To change the OOB IP address, click Edit, and enter the fields:
– Interface — Always displays OOB.
– DHCP IPv4Interface — Select to acquire the IP address dynamically
from a DHCP server.