HP ProCurve 1600M, Руководство по управлению и настройке

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Port Traffic Controls
Jumbo Frames
Enabling or Disabling Jumbo Traffic on a VLAN
Syntax: vlan < vid > jumbo
[ no ] vlan < vid > jumbo
Configures the specified VLAN to allow jumbo frames on all
ports on the switch that belong to that VLAN. If the VLAN is
not already configured on the switch,
vlan < vid > jumbo
also
creates the VLAN. Note that a port belonging to one jumbo
VLAN can receive jumbo frames through any other VLAN
statically configured on the switch, regardless of whether the
other VLAN is enabled for jumbo frames. The
[no]
form of the
command disables inbound jumbo traffic on all ports in the
specified VLAN that do not also belong to another VLAN that
is enabled for jumbo traffic. In a VLAN context, the command
forms are
jumbo
and
no jumbo
. (Default: Jumbos disabled on
the specified VLAN.)
Operating Notes for Jumbo Traffic-Handling
■ ProCurve does not recommend configuring a voice VLAN to accept jumbo
frames. Voice VLAN frames are typically small, and allowing a voice VLAN
to accept jumbo frame traffic can degrade the voice transmission perfor­
mance.
■ You can configure the default, primary, and/or (if configured) the manage­
ment VLAN to accept jumbo frames on all ports belonging to the VLAN.
■ When the switch applies the default MTU (1522-bytes) to a VLAN, all ports
in the VLAN can receive incoming frames of up to 1522 bytes in length.
When the switch applies the jumbo MTU (9220 bytes) to a VLAN, all ports
in that VLAN can receive incoming frames of up to 9220 bytes in length.
A port receiving frames exceeding the applicable MTU drops such frames,
causing the switch to generate an Event Log message and increment the
“Giant Rx” counter (displayed by
show interfaces < port-list >
).
■ The switch allows flow control and jumbo frame capability to co-exist on
a port.
■ The default MTU is 1522 bytes (including 4 bytes for the VLAN tag). The
jumbo MTU is 9220 bytes (including 4 bytes for the VLAN tag).
■ When a port is not a member of any jumbo-enabled VLAN, it drops all
jumbo traffic. If the port is receiving “excessive” inbound jumbo traffic,
the port generates an Event Log message to notify you of this condition.
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