Jumbo Frames; Editing The Nic Frame Size - HP StorageWorks P4000 User Manual

Increasing the frame size improves data transfer speed by allowing larger packets to be transferred
over the network and by decreasing the CPU processing time required to transfer data. However,
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 you want to edit.
5. Click TCP Status Tasks, and select Edit.
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