Data Center, Professional Free Sample Questions

A financial services firm is deploying a new IP fabric for high-frequency trading applications that rely on RoCEv2. The lead architect has mandated the use of Explicit Congestion Notification (ECN) to manage incipient congestion. During testing, engineers notice that while ECN is marking packets correctly on the leaf switches, the upstream spine switches are not reacting to these markings, leading to congestion drops. Which configuration stanza is missing on the spine switches to enable them to participate in the ECN congestion management process?

You are designing a data center interconnect (DCI) solution using EVPN Type 5 routes between two geographically separate sites. The goal is to provide Layer 3 connectivity for multiple tenants, each within their own VRF. For tenancy and routing policy control, which two components are essential for uniquely identifying and controlling the advertisement of IP prefixes across the DCI link? (Select TWO)

A university is deploying a multi-tenant data center to serve different academic departments. The 'Engineering' VRF and the 'Research' VRF must be completely isolated. However, both departments need access to a shared 'HPC-Cluster' service located in a separate VRF. Which technique should be used on the border leaf switches to allow this specific, controlled communication while maintaining default isolation?

True or False: When using Zero-Touch Provisioning (ZTP) for a Juniper QFX switch, the DHCP server can provide the switch with both a configuration file and a software image location in a single DHCP offer message.

An administrator is troubleshooting an EVPN-VXLAN fabric where hosts in VNI 10100 can communicate with each other, but they cannot reach hosts in VNI 10200 within the same tenant VRF. The fabric uses a symmetric IRB model. The administrator confirms that the IRB interfaces are correctly configured on the leaf switches. What is a likely missing piece of configuration causing this inter-VNI routing failure?

A network architect is troubleshooting poor ECMP load-balancing in a spine-leaf fabric. Traffic from a single high-volume flow between two servers is consistently using only one of the available four paths to the spine. The architect wants to ensure that traffic is balanced based on more than just source/destination IP addresses. Which configuration change will achieve per-packet load balancing for all traffic?

When troubleshooting BUM (Broadcast, Unknown Unicast, Multicast) traffic in an EVPN-VXLAN fabric that uses ingress replication, where does the traffic replication occur and which EVPN route type is used to build the list of remote VTEPs?

A cloud provider is using Group-Based Policy (GBP) to enforce micro-segmentation in their multi-tenant EVPN-VXLAN fabric. A new security requirement states that web servers (GBP Tag 10) can initiate connections to database servers (GBP Tag 20), but database servers cannot initiate connections back to the web servers. How is this unidirectional policy typically enforced within the fabric?

Case Study

A healthcare provider, "Veridian Health," is modernizing its primary data center and building a new disaster recovery (DR) site. Both sites are built as EVPN-VXLAN fabrics using QFX Series switches in a spine-leaf topology. The primary goal is to provide seamless workload mobility and active-active access to critical applications hosted in both locations.

The network team has chosen to implement a Layer 3 DCI using EVPN Type 5 routes. The design uses two QFX10002 switches at each site as DCI gateways. Tenant VRFs from the local fabric are extended to the DCI gateways. The gateways at each site peer with each other over a dedicated dark fiber link.

During testing, the team observes that while tenants can communicate with their counterparts in the other DC, all traffic from the DR site to the primary site is taking a suboptimal, higher-latency path through a backup MPLS link instead of the primary dark fiber link. Both links are advertising the tenant prefixes via EBGP.

What is the most likely cause and the best practice solution to ensure traffic prefers the primary dark fiber link?

A network engineer is configuring a new leaf switch using Zero-Touch Provisioning (ZTP). The switch successfully obtains an IP address from DHCP but fails to download its configuration file. The DHCP server is confirmed to be sending the correct file path in DHCP Option 67. The file is hosted on a central TFTP server. What is the MOST likely cause of this ZTP failure?