HP Virtual Connect: Common Myths, Misperceptions, and Objections, Second Edition

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have an impact on the performance of the network or storage switch. Alternatively, VC’s use
of managed MAC addresses and WWNs means the server actually transmits and receives
using the VC managed address. No device on the network (VC or switch) is required to
manipulate the server’s frames. This results in absolutely no performance impact on the
network.
#29: DHCP Option 82 provides the same server redundancy features as
Virtual Connect
Incorrect: DHCP Option 82 only ensures that any NIC port connected to a particular switch port will
receive a given IP address. This is only good for maintaining a constant IP address for server rip-n-
replace. Alternatively, VC’s MAC and WWN address management allows a server blade to be
replaced, or moved, or added anytime and anywhere within the VC Domain or across multiple blade
enclosures. In addition, VC Managed MAC addresses, WWNs, server serial numbers, and UUIDs
ensure application licensing, and other OS Image settings, aren’t affected by any of these changes.
DHCP Option 82 - simply makes sure that any NIC that plugs into Switch X, Port Y receives IP
address Z. This only maintains an IP address for rip-n-replace.
Table 3. DHCP Option 82 Comparison
DHCP Option 82
Does:
• Does keep IP the same for any device that connects its NIC to the
specific switch port
DHCP Option 82
Doesn’t
• Doesn’t provide flexibility
o Doesn't allow server administrator alone to move a server to
a different slot in the enclosure or across the data center
• Doesn't keep the server serial number the same afte
r hardware
replacement.
o Can cause problems with application licensing if application
uses server serial number as part of license data
• Doesn't keep the server UUID the same after hardware replacement.
• Doesn't keep the server MAC addresses the same after hardware
replacement.
o Can cause problems with application licensing if application
uses server's MAC address as part of license data
•
Doesn't keep the server WWNs the same after hardware
replacement.
•
Doesn't keep Fibre Channel boot parameters the same after
hardware replacement
• Doesn’t keep PXE boot order configuration in BIOS after hardware
Virtual Connect – in addition to moving VLAN and SAN assignments with an OS image across
any physical blade within the data center, Virtual Connect also manages a server’s internal and
external identity so that hardware changes are transparent to the OS and to the external LAN and
SAN.
Table 4. VC Comparison
Virtual Connect
Does:
• Does keep IP the same for any server NIC when using VC MAC
addresses and DHCP reservations.
• Does provides flexibility
o Does allows server administrator alone to move a server to a
different slot in the enclosure or across the data center
o
Keeps the same VLAN assignments with the server