Huawei quidway s7700 - SEP Features Supported by the S7700

10.1.2 SEP Features Supported by the S7700
This section describes SEP features supported by the S7700 from the perspective of SEP
configuration logic. Familiarizing yourself with SEP configuration logic helps you complete
configuration tasks quickly and efficiently.
SEP configuration roadmap is as follows:
1. After basic SEP functions are configured on devices, the devices start the SEP negotiation.
One of the last two interfaces that complete neighbor negotiation is blocked to eliminate
redundant links.
NOTE
When logging in to nodes on a SEP semi-ring through Telnet to configure them, note the following
points:
l VLANIF interfaces and their IP address need to be configured, because these nodes are Layer 2
devices. The VLANs to which these VLANIF interfaces correspond must be mapped to the SEP
protection instance.
l Basic SEP functions need to be configured from the node at one end of the semi-ring to the node
at the other end of the semi-ring.
2. In some cases, however, the blocked interface obtained through the SEP calculation may
not be the one you expect to be blocked. You can specify an interface to block as needed.
3. To implement load balancing and make efficient use of bandwidth, protected instances
need to be deployed on a network running SEP and mappings between protected instances
and VLANs need to be worked out.
4. A SEP network usually needs to work together with another network deployed with other
features. To ensure network reliability, if the topology of either of the networks changes,
the other network must be able to detect the topology change and take measures to
implement reliable data transmission. Therefore, the topology change notification function
needs to be enabled on the network running SEP.
Specifying an Interface to Block
In general, a blocked interface is one of the last two interfaces that complete neighbor negotiation.
In some cases, however, the negotiated blocked interface may not be the one you expect to be
blocked. You specify an interface to block as needed. The designated blocking does not,
however, become effective immediately. A preemption mechanism allows a designated interface
to be blocked instead of a previously blocked interface.
l Interface blocking mode
You can configure an interface blocking mode in order to specify the location of a blocked
interface. Table 10-4 lists interface blocking modes.
Table 10-4 Interface blocking mode
Interface Blocking
Mode
Description
Specifying the interface
with the highest priority
as the blocked interface
Is applicable to a large-scale network.
After fault recovery, the interface with the highest priority in
a SEP segment is designated as the blocked interface. In this
mode, the priorities of the interfaces on the SEP segment need
to be set in advanced.
Quidway S7700 Smart Routing Switch
Configuration Guide - Ethernet 10 SEP Configuration
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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