A mismatch between the AS number defined in ‘routing-options autonomous-system’ and the local-as configured under the BGP peer/group is a common cause for BGP sessions remaining in Active state. The router uses the ‘routing-options autonomous-system’ for certain internal checks, and an inconsistency can prevent session establishment, even if other parameters like IP connectivity are correct.

EVPN Type 3 routes, known as Inclusive Multicast Ethernet Tag routes, are used to dynamically advertise VTEP membership for a given broadcast domain (VLAN/VNI). When a leaf joins a VLAN, it sends a Type 3 route. Spines and other leaves receive this route and can dynamically build their ingress replication lists (also called multicast tunnel endpoints), enabling efficient BUM traffic forwarding without requiring static configuration or a separate underlay multicast protocol.

To permit traffic *from* a logical system *to* the global system (or another logical system), you must configure a unified security policy in the **global system** context. This policy uses the logical system’s security zone as the source zone and the destination zone (e.g., the global system’s zone) as the destination. Security policies are enforced at the point of transition between security zones, which, for inter-logical-system traffic, is handled by the global system’s policy framework.

On MX Series routers, to use a scheduler-map for shaping (hierarchical scheduling), you must first enable the hierarchy by configuring an overall shaping rate at the physical interface level using ‘set class-of-service interfaces shaping-rate’. The scheduler-map is then attached under this hierarchical node. Without the interface-level ‘shaping-rate’, the scheduler-map controls relative bandwidth between queues but does not impose an absolute upper limit on the interface’s total output.

EVPN Type 5 routes are IP Prefix Advertisement routes. Their primary purpose is to extend IP routing across the EVPN-VXLAN fabric for prefixes that are not locally connected to a leaf (e.g., prefixes from a WAN router, external firewall, or data center core). When a leaf receives a Type 5 route, it installs the prefix in its routing table with the advertising VTEP as the next-hop, enabling inter-subnet (Layer 3) routing over the VXLAN tunnel.

For DVPN with NHTB, the hub uses BGP to advertise spoke routes within a specific routing instance. The key to dynamic spoke-to-spoke tunnels is that all devices (hub and spokes) must participate in the same BGP community. The ‘community target’ value configured under the dynamic VPN routing instance defines this group. When a spoke receives a BGP route from the hub with this community, it triggers the establishment of a direct IPsec tunnel to the other spoke listed as the next-hop, rather than routing traffic via the hub.

The ‘inet.3’ routing table in Junos is specifically reserved for storing label-switched path (LSP) next-hop information. It contains entries for prefixes that are reachable via an MPLS LSP (e.g., an RSVP or LDP LSP). The primary purpose of this table is to support resolving BGP next-hops over MPLS tunnels (BGP-over-MPLS). When a BGP route has a next-hop that is listed in inet.3, traffic to that BGP prefix will be label-switched through the MPLS core.

Link Aggregation Control Protocol (LACP) requires at least one device on the link to be in ‘active’ mode to initiate the transmission of LACP Protocol Data Units (PDUs). If both ends are set to ‘passive’, they will both wait for the other to send LACP packets, resulting in no protocol communication and the aggregated Ethernet interface failing to come up. The correct configurations are active/passive or active/active.

The ‘reboot’ option appended to the ‘request system software add’ command instructs the device to automatically reboot into the new software after the package is successfully validated, unpacked, and copied to the alternate root file system. This automates the final step of the upgrade process. Without this option, the administrator must manually reboot the device with ‘request system reboot’ to activate the new software.

A mismatch between the AS number defined in ‘routing-options autonomous-system’ and the local-as configured under the BGP peer/group is a common cause for BGP sessions remaining in Active state. The router uses the ‘routing-options autonomous-system’ for certain internal checks, and an inconsistency can prevent session establishment, even if other parameters like IP connectivity are correct.0