Management and Configuration Guide K/KA/KB.15.15

NOTE: The jumbo max-frame-size is set on a GLOBAL level.
Configuring IP MTU
NOTE: The following feature is available on the switches covered in this guide. jumbos support
is required for this feature. On switches that do not support this command, the IP MTU value is
derived from the maximum frame size and is not configurable.
You can set the IP MTU globally by entering this command. The value of max-frame-size must
be greater than or equal to 18 bytes more than the value selected for ip-mtu. For example, if
ip-mtu is set to 8964, the max-frame-size is configured as 8982.
Syntax
jumbo ip-mtu size
Globally sets the IP MTU size. Values range between 1500 and 9198 bytes. This value must be
18 bytes less than the value of max-frame-size.
(Default: 9198 bytes)
Viewing the maximum frame size
Use the show jumbos command to display the globally configured untagged maximum frame
size for the switch, as shown in the following example.
(HP_Switch_name#) show jumbos
Jumbos Global Values
Configured : MaxFrameSize : 9216 Ip-MTU : 9198
In Use : MaxFrameSize : 9216 Ip-MTU : 9198
Operating notes for maximum frame size
• When you set a maximum frame size for jumbo frames, it must be on a global level. You
cannot use the jumbo max-frame-size command on a per-port or per-VLAN basis.
• The original way to configure jumbo frames remains the same, which is per-VLAN, but you
cannot set a maximum frame size per-VLAN.
• Jumbo support must be enabled for a VLAN from the CLI or through SNMP.
• Setting the maximum frame size does not require a reboot.
• When you upgrade to a version of software that supports setting the maximum frame size
from a version that did not, the max-frame-size value is set automatically to 9216 bytes.
• Configuring a jumbo maximum frame size on a VLAN allows frames up to max-frame-size
even though other VLANs of which the port is a member are not enabled for jumbo support.
All traffic rate-limiting
Rate-limiting for all traffic operates on a per-port basis to allow only the specified bandwidth to be
used for inbound or outbound traffic. When traffic exceeds the configured limit, it is dropped. This
effectively sets a usage level on a given port and is a tool for enforcing maximum service level
commitments granted to network users. This feature operates on a per-port level and is not
configurable on port trunks. Rate-limiting is designed to be applied at the network edge to limit
All traffic rate-limiting 183