Link Mode - Cisco SCE 2000 4xGBE Installation And Configuration Manual

Chapter 6 Cabling the Line Ports and Completing the Installation

Link Mode

The SCE 2000 platform has an internal hardware card used to maintain the links even when the
SCE 2000 platform fails. This hardware card has four possible modes of operation:
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Normally, the link mode is selected by the SCE 2000 platform software according to the
configured connection-mode. However, the link-mode command can be used to enforce a
specific desired mode. This may be useful when debugging the network, or in cases where we
would like the SCE 2000 platform just to forward the traffic. (Note that this is only relevant to
inline topologies even though the configuration is available also when in receive-only mode.)
The following link mode options are available:
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This does not affect the redundancy states.
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Sniffing is permitted to be configured for for all links, only (use the all-links option).
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Note the following recommendations and restrictions:
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OL-7824-04
bypass
forwarding
cutoff
sniffing
Forwarding — forwards traffic on the specified link to the SCE 2000 platform for
processing.
Bypass — stops all forwarding of traffic on the specified link to the SCE 2000 platform.
Traffic still flows on the link, but is not processed in any way by the SCE 2000 platform.
Sniffing — allows the SCE 2000 platform to forward traffic on the specified link through
the bypass mechanism while still analyzing the traffic passively.
Cutoff — completely cuts off flow of traffic through the specified link.
Since the SCE 1000 platform has only one link, the link is not specified.
Since the SCE 2000 platforms have more than one link, it is required to specify the link.
The link designations are different for the GBE and FE platforms, as follows:
• SCE 2000 4xGBE — GBE1-GBE2/GBE3-GBE4
• SCE 2000 4/8xFE — LINK1/LINK2
Use the 'all-links' option to configure the link mode for all links (SCE 2000
platforms only).
It is recommended that both links be configured together. Use the all-links option.
Link mode is relevant only to inline topologies.
It is recommended that in cascaded topologies, both SCE 2000 platforms be configured for
the same link mode, otherwise the service will be unpredictable.
Sniffing can only be configured for all links, therefore, to configure sniffing, the all-links
option is required, not just recommended.
The default link mode is forwarding. When other link modes are selected, active service
control is not available and any service control configuration will not be applicable.
Cisco SCE 2000 4xGBE Installation and Configuration Guide
Installing a Cascaded System
6-13