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What’s Changed in Release 21.1R2


  • Minimum auto-recovery time reduced for duplicate MAC address detection (ACX Series, PTX Series and QFX Series)—Junos OS has changed the minimum value allowed for auto-recovery time for duplicate MAC address detection from 5 minutes to 1 minute. The auto-recovery time is the length of time that the device suppresses a duplicate MAC address. Reducing the auto-recovery time allows customers to quickly recover from a MAC address duplication state. You configure the auto-recovery-time option under the duplicate-mac-detection statement at the edit routing-instances routing-instance-name protocols evpn or edit protocols evpn hierarchy.

    [See Changing Duplicate MAC Address Detection Settings .]

General Routing

  • Enhancement to the default remnant-holdtime (Junos OS Evolved platforms: QFX5130-32CD, and QFX5220)— Starting this release, the default remnant-holdtime has been increased from 180 seconds to 300 seconds. This provides sufficient time for protocols to start and sync routes from neighbors in a scaled environment, during rpd restart. You can configure remnant-holdtime at the edit routing-options forwarding-table hierarchy level.

    See forwarding-table .]

Network Management and Monitoring

  • Changes in contextEngineID for SNMPv3 INFORMS (ACX Series, PTX Series, and QFX Series)— Now the contextEngineID of SNMPv3 INFORMS is set to the local engine-id of Junos devices. In earlier releases, the contextEngineID of SNMPv3 INFORMS was set to remote engine-id.

    [See SNMP MIBs and Traps Supported by Junos OS.]