HP LeftHand P4000 Virtual SAN Appliance Software - Manual (Page 52)

increasing the frame size requires that routers, switches, and other devices on your network support
that frame size.
NOTE: Increasing the frame size can cause decreased performance and other network problems
if routers, switches, or other devices on your network do not support frame sizes greater than 1500
bytes. If you are unsure about whether your routers and other devices support larger frame sizes,
keep the frame size at the default setting.
If you edit the frame size on a disabled or failed NIC, the new setting will not be applied until the
NIC is enabled or connectivity is restored.
To avoid potential connectivity and performance problems with other devices on your network,
keep the frame size at the default setting. The frame size on the storage system should correspond
to the frame size on Windows and Linux application servers. If you decide to change the frame
size, set the same frame size on all storage systems on the network, and set compatible frame
sizes on all clients that access the storage systems.
Consult with your network administrator for recommended storage system frame sizes and the
corresponding frame sizes in bytes for Windows and Linux clients in your environment.
Jumbo frames
Frame sizes that are greater than 1500 bytes are called jumbo frames. Jumbo frames must be
supported and configured on each Windows or Linux client accessing the storage system and also
on each network switch between the storage system and the Windows or Linux clients.
Jumbo frames can co-exist with 1500 byte frames on the same subnet if the following conditions
are met:
•
Every device downstream of the storage system on the subnet must support jumbo frames.
•
If you are using 802.1q virtual LANs, jumbo frames and nonjumbo frames must be segregated
into separate VLANs.
NOTE: The frame size for a bonded logical interface must be equal to the frame size of the
NICs in the bond.
Editing the NIC frame size
To edit the frame size:
1. In the navigation window, select a storage system and log in.
2. Open the tree, and select the TCP/IP Network category.
3. Select the TCP Status tab.
4. Select the interface to edit.
5. Click TCP Status Tasks, and select Edit.
6. Select Set To in the Frame Size section.
7. Enter a value between 1500 and 9000 bytes in the Set To field.
8. Click OK.
A series of status messages display. Then the changed setting appears in the TCP status report.
NOTE: You can also use the Configuration Interface to edit the frame size.
Changing NIC flow control
Flow control on the NICs prevents data transmission overruns that result in packets being dropped.
With flow-control enabled, network packets that would otherwise be dropped will not have to be
retransmitted. Auto-negotiate is the default setting for NIC flow control. You can change the setting
to manually choose the transmit and receive settings for the NIC.
52 Managing the network