Loopback; Mtu - HP 6600 Command Reference Manual

<Sysname> system-view
[Sysname] interface serial 1/2/0
[Sysname-Serial1/2/0] itf number 5

loopback

Use loopback to enable loopback on the serial interface.
Use undo loopback to restore the default.
Syntax
loopback
undo loopback
Default
Loopback is disabled.
Views
Serial interface view
Default command level
2: System level
Usage guidelines
Loopback is intended for test use. Disable loopback in other cases.
Examples
# Enable loopback on interface Serial 1/0/0.
<Sysname> system-view
[Sysname] interface serial 1/0/0
[Sysname-Serial1/0/0] loopback

mtu

Use mtu to set the MTU for an interface.
Use undo mtu to restore the default.
Syntax
mtu size
undo mtu
Default
The MTU of an interface is 1500 bytes.
Views
Serial interface view
Default command level
2: System level
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