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What’s Changed in Release 21.1R2


  • IGMP snooping options has changed hierarchy level—Junos OS has moved the following options from the [edit protocols igmp-snooping] hierarchy to [edit protocols igmp-snooping vlan vlan-name] hierarchy and [edit routing-instances evpn protocols igmp-snooping] hierarchy to [edit routing-instances evpn protocols igmp-snooping vlan vlan-name] hierarchy

  • query-interval






  • Support for displaying SVLBNH information—You can now view shared VXLAN load balancing next hop (SVLBNH) information when you display the VXLAN tunnel endpoint information for a specified ESI and routing instance by using show ethernet-switching vxlan-tunnel-end-point esi esi-identifier esi-identifier instance instance svlbnh command.

General Routing

  • Configure internal IPsec authentication algorithm (EX Series)—You can configure the algorithm hmac-sha-256-128 at the [edit security ipsec internal security-association manual direction bidirectional authentication algorithm] hierarchy level for internal IP security (IPsec) authentication. In earlier releases, you could configure the algorithm hmac-sha-256-128 for MX Series devices only.

Interfaces and Chassis

  • Blocking duplicate IP detection in the same routing instance (ACX Series, EX Series, MX Series, NFX Series, PTX Series, QFX Series, and SRX Series)--Junos will no longer accept duplicate IPs between different logical interfaces in the same routing instance. Refer to the table mentioned in the topic inet (interfaces). When you try to configure same IP on two logical interfaces inside same routing instance, the commit will be blocked with the error displayed as shown below:[edit] user@host# set interfaces ge-0/0/1 unit 0 family inet address [edit] user@host# commit commit complete [edit] user@host# set interfaces ge-0/0/2 unit 0 family inet address [edit] user@host# commit [edit interfaces ge-0/0/2 unit 0 family inet] 'address' identical local address found on rt_inst default, intfs ge-0/0/2.0 and ge-0/0/1.0, family inet. error: configuration check-out failed.

    [See inet(interfaces).]

Layer 2 Ethernet Services

  • Link selection support for DHCP—We have introduced the link-selection statement at the edit forwarding-options dhcp-relay relay-option-82 hierarchy level, which allows DHCP relay to add suboption 5 to option 82. Suboption 5 allows DHCP proxy clients and relay agents to request an IP address for a specific subnet from a specific IP address range and scope. Prior to this release, the DHCP relay dropped packets during the renewal DHCP process and the DHCP server used the leaf's address as a destination to acknowledge the DHCP renewal message.

    See relay-option-82.

Network Management and Monitoring

  • Change in OID ifHighSpeed—Now, the object identifier (OID) ifHighSpeed displays the negotiated speed once negotiation is completed. If the speed is not negotiated, ifHighSpeed displays the actual maximum speed of the interface. In earlier releases, ifHighSpeed always displayed the actual speed of the interface.

    See SNMP MIBs and Traps Supported by Junos OS.

  • Changes in contextEngineID for SNMPv3 INFORMS (PTX Series, QFX Series, ACX Series, EX Series, MX Series, and SRX 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.