JNCIE-ENT case studies
JNCIE-ENT · Put your knowledge to work in context.
JNCIE-ENT (exam code JPR-946) is the expert-level certification in the enterprise routing and switching track, positioned by Juniper as the pinnacle of that four-step path from JNCIA-Junos through JNCIS-ENT and JNCIP-ENT. It targets engineers who already hold JNCIP-ENT and can deploy, configure, manage and troubleshoot Junos-based enterprise routing and switching platforms without hand-holding. The exam is a six-hour hands-on lab: you build an enterprise network infrastructure of multiple routers and switching devices, perform system configuration on all of them, and configure protocols and features including IGPs, BGP, EVPN, Layer 2 features, routing policies and class of service. It is delivered by Juniper Networks in English only, and the published lab environment runs vEX Virtual Switch 25.2R1, vSRX Virtual Firewall 25.2R1 and vMX Virtual Router 23.2R2. The JNCIE-ENT case studies are 5 cases and about 3,012 words.
1SNMP Polling Collapse After EVPN-VXLAN Rollout
A network team manages 240 Juniper EX and QFX switches from one Nagios XI server. Polling uses SNMPv3 authPriv at a 60-second interval and walks ifDescr, ifHCInOctets, jnxOperatingTable, and jnxCosIfqStatsTable on every device.
683 words, about 3 min2MSTP Revision Drift Isolates VLAN 20
A campus runs six EX4650 switches in two 3-member Virtual Chassis, one per building. MSTP uses region name CAMPUS-MSTP, revision 3, MSTI 1 for VLANs 10–19, and MSTI 2 for VLANs 20–29.
646 words, about 3 min3VRRP Master Fights the OSPF Best Path
Two EX4650 distribution switches, DIST-A and DIST-B, serve 20 VLANs with VRRP groups 10–29. DIST-A is master for all groups with priority 200 and preempt; DIST-B is backup with priority 100.
555 words, about 3 min4EVPN ESI-LAG Blackhole After Leaf Reboot
A 2-spine, 4-leaf EVPN-VXLAN fabric uses QFX5120 switches. Leaf L1 and leaf L2 are in the same rack and dual-home a server with an all-active ESI-LAG.
564 words, about 3 min5Voice Starvation During Backup Burst
An EX9200 is the campus WAN edge. The provider handoff is a 1 Gbps Layer 2 VPN on xe-0/0/0.0 and honors 802.1p.
564 words, about 3 min