Cisco 10000 - Manual (Page 394)

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Cisco 10000 Series Router Software Configuration Guide
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Chapter 18 Configuring L2 Virtual Private Networks
Configuration Tasks for L2VPN
Figure 18-5 Remote Link Outage in EoMPLS Wide Area Network
In earlier releases than Cisco IOS Release 12.2(33)SB, the PE2 router did not detect a failed remote link.
Traffic forwarded from CE2 to CE1 is lost until routing or spanning tree protocols detected the down
remote link. If the link was configured with static routing, remote link outage can be difficult to detect
by the L3 routing protocol.
With Any Transport over MPLS (AToM): Remote Ethernet Port Shutdown, the PE2 router detects the
remote link failure and causes a shutdown of the local CE2 Ethernet port. When the remote L2 tunnel
link is restored, the local interface is automatically restored as well. The possibility of data loss is thus
diminished.
With reference to Figure 18-5 , a remote Ethernet shutdown sequence occurs as follows:
1. The remote link between CE1 and PE1 fails.
2. PE2 with remote Ethernet port shutdown enabled detects the remote link failure and disables the
transmit laser on the line card interface connected to CE2.
3. CE2 receives an RX_LOS error alarm causing CE2 to bring down the interface.
4. PE2 maintains its interface with CE2 in an up state.
5. When the remote link and EoMPLS connection is restored, the PE2 router enables the transmit laser.
6. The CE2 router brings up its downed interface.
Restrictions for Configuring Remote Ethernet Port Shutdown
The following restrictions pertain to the Remote Ethernet Port Shutdown feature:
• For Cisco IOS Release 12.2(33) SB, this feature is implemented for port mode Ethernet over MPLS
connections between Cisco 10000 series Ethernet line cards only.
• This feature is not symmetrical if the remote PE router is running an older version of image or is on
another platform that does not support the EoMPLS remote Ethernet port shutdown feature and the
local PE is running an image which supports this feature.
Configuring Remote Ethernet Port Shutdown
By default, the Any Transport over MPLS (AToM): Remote Ethernet Port Shutdown feature is
automatically enabled when an image with this feature supported is loaded on the Cisco 10000 series
router. However, to enable the Remote Ethernet Port Shutdown feature, enter the remote link failure
notification command, as shown in
Example 18-18 .
To disable the feature, enter the no remote link failure notification command ( Example 18-19 ).
Example 18-18 Enabling Remote Ethernet Port Shutdown under the Xconnect Configuration
pseudowire-class eompls
Customer Edge 1 Customer Edge 2
X
Ethernet over MPLS
(EoMPLS)
Ethernet Ethernet
Provider Edge 1
Cisco 10000
Series Router
Provider Edge 2
Cisco 10000
Series Router
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