JNCIE-SP flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

commit confirmed

Junos commit mode that applies configuration temporarily and automatically rolls back unless a confirming commit is issued within the specified minutes.

Login class permissions

Junos login classes assign permissions such as configure, view, and shell; allow-configuration and deny-configuration regexes scope which hierarchy paths the class may edit.

SNMPv3 USM

User-based Security Model for SNMPv3; requires a local-engine user with authentication (SHA) and optional privacy keys, plus VACM access groups for MIB views.

Dual-root software upgrade

Junos upgrade process using request system software add, request system snapshot to sync the alternate root, and request system reboot media disk to boot it.

OSPF virtual link

Configuration under a non-backbone area that logically connects it to area 0 through a transit area, restoring backbone connectivity for an isolated ABR.

IS-IS L1/L2

L1 routers flood intra-area routes; L2 routers form the backbone and carry inter-area prefixes. level 1 disable makes a pure L2 router.

Junos policy evaluation

Policy statements contain ordered terms; each term's from conditions are matched top-down, first match wins, and an implicit deny follows without an accept term.

route-filter match types

Policy match keywords exact, longer, orlonger, upto, prefix-length-range, and through define which prefixes a route-filter term matches relative to the stated prefix.

BGP best-path order

Junos selection order: weight, local-preference, locally originated, AS-path length, origin, MED, eBGP over iBGP, IGP metric, router ID, cluster list length.

Route reflector cluster

An RR reflects client routes to other clients and non-clients; cluster ID identifies the cluster, and no-client-reflect disables client-to-client reflection.

BGP confederation

Splits one AS into sub-AS members that run iBGP internally; confederation peers use type external with the confederation keyword and AS path shows the confederation AS.

BGP damping

Suppresses flapping routes using half-life, reuse, suppress, and max-suppress thresholds; a route is penalized on each withdrawal and restored after decay.

LDP label database

show ldp database lists inbound and outbound label bindings per interface; LDP advertises labels for IGP routes and the loopback when ldp is enabled on lo0.0.

RSVP-TE LSP signaling

RSVP reserves bandwidth along an explicit path; LSP parameters include bandwidth, setup-priority, hold-priority, and primary/standby paths.

inet.3 table

Junos routing table holding label-switched routes learned from RSVP-TE and LDP; BGP next hops resolve over inet.3 when traffic-engineering bgp-igp is configured.

MPLS label stacking

Outer transport label (LDP or RSVP) is pushed over an inner service label (VPN or VC); mpls.0 shows swap, pop, and push operations.

VRF route target

Extended community controlling VPN route import and export; vrf-target sets both, while vrf-import and vrf-export policies allow selective leaking.

Inter-AS Option B

MP-eBGP between ASBRs carrying family inet-vpn; ASBRs exchange VPN-IPv4 routes and rewrite next hops, requiring VRFs or vrf-table-label on ASBRs.

Inter-AS Option C

MP-eBGP between PE routers with family inet labeled-unicast between ASBRs; the ASBRs forward labeled packets without maintaining customer VRFs.

Carrier-of-carriers VPN

The carrier provides a VRF with vrf-target and vrf-table-label but does not import customer route targets; customer routes travel as VPN routes end to end.

Hub-and-spoke VPN

Hub VRF exports a route target all spokes import; each spoke exports a distinct target the hub imports, forcing spoke-to-spoke traffic through the hub.

VPLS site configuration

BGP-signaled VPLS requires instance-type vpls, vpls-id, route-distinguisher, and protocols vpls site with site-identifier and interface.

EVPN-MPLS encapsulation

Set protocols evpn encapsulation mpls and instance-type evpn with vlan-id, route-distinguisher, vrf-target, and protocols evpn interface to build an EVPN-MPLS instance.

EVPN-VXLAN VTEP

switch-options vtep-source-interface lo0.0 sets the tunnel endpoint; routing-instances evpn vxlan vni maps the VLAN to a VXLAN network identifier.

EVPN Ethernet Segment

An ESI identifies a multihomed segment; EVPN advertises Ethernet Segment routes and elects a Designated Forwarder per segment for BUM traffic.

PIM-SM rendezvous point

Shared-tree root configured with protocols pim rp static address or rp local address; sources register with the RP and receivers join the shared tree.

PIM-SSM

Source-specific multicast using (S,G) joins with IGMPv3; protocols pim ssm is configured and no rendezvous point is required for the data path.

MSDP

Multicast Source Discovery Protocol connects rendezvous points across PIM domains; peers exchange active source information so receivers can join remote sources.

Multicast VPN provider tunnel

instance-type mvpn with protocols mvpn and provider-tunnel rsvp-te or ldp-p2mp carries customer multicast traffic across the provider core.

BFD liveness detection

protocols bfd min-interval and multiplier set timers; bfd-liveness-detection under OSPF, IS-IS, or BGP tears down the session on sub-second failure.

NSR versus NSB

Nonstop routing keeps routing protocol state synchronized to the backup RE; nonstop bridging does the same for Layer 2 protocols such as STP.

CoS scheduler map

Maps forwarding classes to schedulers defining transmit rate, buffer size, and drop profile; applied to interfaces with class-of-service interfaces scheduler-map.

Firewall filter actions

Junos filter actions include accept, discard, reject, count, policer, and log; counters are verified with show firewall filter name.