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Home Documentation Junos OS Junos CLI Reference CLI Reference E

Junos CLI Reference

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Junos CLI Reference
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{ "lLangCode": "en", "lName": "English", "lCountryCode": "us", "transcode": "en_US" }
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enforce-first-as

date_range 19-Nov-23
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Syntax

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enforce-first-as;

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[edit fabric protocols bgp],   
[edit fabric protocols bgp group group_name],      
[edit fabric protocols bgp group group_name neighbor address],  
[edit logical-systems name],
[edit logical-systems name protocols bgp],     
[edit logical-systems name protocols bgp group group_name],     
[edit logical-systems name protocols bgp group group_name neighbor address],       
[edit logical-systems name routing-instances instance_name protocols bgp],      
[edit logical-systems name routing-instances instance_name protocols bgp group group_name],    
[edit logical-systems name routing-instances instance_name protocols bgp group group_name  neighbor address],
[edit protocols bgp],
[edit protocols bgp group group-name],
[edit protocols bgp group group-name neighbor neighbor-address],
[edit routing-instances instance_name protocols bgp],      
[edit routing-instances instance_name protocols bgp group group_name],      
[edit routing-instances instance_name protocols bgp group group_name neighbor address]

Description

Enforce that the first (left-most) autonomous system number (ASN) in AS-path is the previous neighbor's ASN. When configured, this statement enforces that as the domain is transited, the routes received from an EBGP peer have the peer’s ASN in the left-most position of the AS path.

Required Privilege Level

routing—To view this statement in the configuration.

routing-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 15.1.

Related Documentation

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