, if a link fault occurs in the SEP segment, P1 on Router1 and P1 on
Router5 receive fault notification packets or P1 on LSW5 does not receive primary edge
interface election packets within a specified period. Then P1 on Router1 becomes the secondary
edge interface. Consequently, two secondary edge interfaces exist in the SEP segment and
periodically send primary edge interface election packets.
When all link faults in the SEP segment are rectified, the two secondary edge interfaces can
receive primary edge interface election packets and elect a new primary edge interface within a
configured interval (1s by default).
Specifying an Interface to Block
Normally, a blocked interface is one of the two interfaces that complete neighbor negotiations
last. In some cases, however, the negotiated blocked interface may not be the required one. You
can specify an interface to block according to network requirements. The specified interface
preempts to be the blocked interface only after the preemption mechanism takes effect.
l
Interface blocking mode
You can configure the interface blocking mode to specify a blocked interface.
lists interface blocking modes.
Table 8-5
Interface blocking mode
Interface Blocking Mode
Description
Specify the interface with the
highest priority as the
blocked interface.
SEP compares interface priorities as follows:
1. Compares configured interface priority values. A
larger value indicates a higher priority.
2. Compares bridge MAC addresses of interfaces with
same priority values. A smaller bridge MAC address
indicates a higher priority.
3. Compares interface numbers of interfaces with
identical bridge MAC addresses. A smaller interface
number indicates a higher priority.
Specify the interface in the
middle of a SEP segment as
the blocked interface.
-
Specify a blocked interface
based on the configured hop
count.
SEP sets the hop count of the primary edge interface to
1 and the hop count of the neighboring interface of the
primary interface to 2. Hop counts of other interfaces
increase by steps of 1 in the downstream direction of the
primary edge interface.
Huawei AR530&AR550 Series Industrial Switch Routers
Configuration Guide - Ethernet Switching
8 SEP Configuration
Issue 01 (2014-11-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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