User Manual
UMN:CLI
V8102
387
9.4.10
Restarting Protocol Migration
MSTP protocol has a backward compatibility. MSTP is compatible with STP and RSTP. If
some other bridge runs on STP mode and sends the BPDU version of STP or RSTP,
MSTP automatically changes to STP mode. But STP mode cannot be changed to MSTP
mode automatically. If administrator wants to change network topology to MSTP mode,
administrator has to clear the previously detected detected protocol manually.
To prevent this, the V8102 provides the
clear spanning-tree detected-protocols
com-
mand. If you enable this command, the switch checks STP protocol packet once again. To
clear configured Restarting Protocol Migration, use the following command.
Command
Mode
Description
clear spanning-tree detected-
protocols
Global
Interface
[XE/GE]
Restarts protocol migration function.
9.4.11
Loop Back Detection
The problem occurs because the keepalive packet is looped back to the port that sent the
keepalive. Keepalives are sent on the switches in order to prevent loops in the network.
You see this problem on the device that detects and breaks the loop, but not on the de-
vice that causes the loop.
To enable error-disable detection for loop back cause, use the following command.
Command
Mode
Description
errdisable detect cause loopback
Global
Enables error-disable detection for loop
back cause
no errdisable detect cause loopback
Disables error-disable detection for loop
back cause
To display the status of error-disable cause, use the following command.
Command
Mode
Description
show errdisable detect cause
Global
Shows status of error-disable causes
To enable/disable the error-disable recovery function for loop back cause, use the follow-
ing command.
Command
Mode
Description
errdisable recovery cause all
Global
Enables the recovery function for all
cause
errdisable recovery cause loopback
Enables the recovery function for loop
back error-disable cause
errdisable recovery cause bpduguard
Enables
the
recovery
function
for
bpduguard error-disable cause
