R2511-HP MSR Router Series Interface Command Reference(V5)

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Usage guidelines
FE3 mode is a non-standard E3 application mode. In this mode, the subrate level setting varies with
vendors. You can use the fe3 command to make the device to be compatible with devices of other
vendors operating in specific FE3 DSU modes.
This command is only applicable to CE3 modules that support FE3.
This command is available only in E3 mode.
As for the fe3 subrate command, the actual subrate usually is not exactly the one set by the command.
After you set the subrate by using the fe3 subrate command, the CE3 interface searches the subrate
levels corresponding to the DSU mode it is operating in and selects the one that is closest to that set by
the command as its subrate. The device then adjusts the hardware to allow for the subrate.
You can use the display interface serial interface-number:0 command to check the DSU mode setting,
the subrate, the actual rate, and the baudrate of a CE3 interface. The actual rate does not include the
overhead bits, and the baudrate is the actual E3 line rate (34368 kbps), with the overhead bits counted
in.
Examples
# Configure E3 2/0 interface to operate in the FE3 mode, setting the DSU mode to 1 and the subrate to
3000 kbps.
<Sysname> system-view
[Sysname] controller e3 2/0
[Sysname-E3 2/0] using e3
[Sysname-E3 2/0] fe3 dsu-mode 1
[Sysname-E3 2/0] fe3 subrate 3000
loopback (CE3 interface)
Use loopback to configure the loopback mode of the CE3 interface.
Use undo loopback to restore the default.
Syntax
loopback { local | payload | remote }
undo loopback
Default
Loopback is disabled on the CE3 interface.
Views
CE3 interface view
Default command level
2: System level
Parameters
local: Enables internal loopback on the CE3 interface.
payload: Enables external payload loopback on the CE3 interface.
remote: Enables external loopback on the CE3 interface.