Which of the following routing protocols is not capable of avoiding credit loops?
Correct Answer: C
TheMINHOProuting protocol, while efficient in finding minimal paths, does not inherently prevent credit loops. This can lead to deadlocks in the network. In contrast, routing protocols like UPDOWN and FAT TREE are designed to avoid such loops, ensuring more reliable network operation. Reference:Optimized Routing for Large-Scale InfiniBand Networks
Question 22
When upgrading DOCA on a BlueField DPU, what command should first be run on the host?
Correct Answer: B
Before upgrading the DOCA SDK on aBlueField DPU, it ismandatory to uninstall the existing OFED driversto prevent compatibility conflicts. From theNVIDIA DOCA Installation Guide: "Before upgrading DOCA or BlueField-related software, you must remove existing OFED packages using: /usr/sbin/ofed_uninstall.sh -force." This ensures: * Clean driver state * No residual kernel modules or userspace libraries * Proper registration of new DOCA/OFED versions Incorrect Options: * AandCmay not resolve conflicts. * Dinstalls but doesn't remove conflicting packages. Reference: DOCA SDK Installation - Uninstall OFED Requirement
Question 23
You are troubleshooting connectivity issues in your InfiniBand network and need to test basic connectivity between nodes. Which command should you use to test basic connectivity between InfiniBand nodes?
Correct Answer: A
The tool specifically designed for testingInfiniBand connectivityis **ibping**. It functions similarly to the traditional ping utility but is optimized forInfiniBand fabrics. From theNVIDIA InfiniBand Diagnostic Utilities Documentation: "ibping tests the connectivity of InfiniBand nodes by sending management datagrams (MADs) and verifying the response from the destination LID or GUID." * Tests basicnode-to-nodereachability * Supports testing viaLID, GUID, orport number * Helps verify subnet manager routing and fabric health Incorrect Options: * pingandtracerouteare IP-based, not fabric-aware. * ibnetdiscovermaps topology but doesn't test live connectivity. Reference: InfiniBand Diagnostic Tools - ibping
Question 24
When creating a simulation in NVIDIA AIR, what syntax would you use to define a link between port 1 on spine-01 and port 41 on gpu-leaf-01?
Correct Answer: A
NVIDIA AIR (AI-Ready Infrastructure) is a cloud-based simulation platform designed to model and validate data center network deployments, including Spectrum-X Ethernet networks, using realistic topologies and configurations. When creating a custom topology in NVIDIA AIR, users can define network links between devices (e.g., spine and leaf switches) using a DOT file format, which is based on the Graphviz graph visualization software. The question asks for the correct syntax to define a link between port 1 on a spine switch (spine-01) and port 41 on a leaf switch (gpu-leaf-01) in a NVIDIA AIR simulation. According to NVIDIA's official NVIDIA AIR documentation, the DOT file format is used to specify network topologies, including nodes (devices) and links (connections between ports). The syntax for defining a link in a DOT file uses a double dash (--) to indicate a connection between two ports, with each port specified in the format "<node>":"<port>". For Spectrum-X networks, which typically use Cumulus Linux or SONiC on NVIDIA Spectrum switches, ports are commonly labeled as swpX (switch port X) rather than ethX (Ethernet interface), especially for switch-to- switch connections in a leaf-spine topology. The correct syntax for the link between port 1 on spine-01 and port 41 on gpu-leaf-01 is: "spine-01":"swp01" -- "gpu-leaf-01":"swp41" This syntax uses swp01 and swp41 to denote switch ports, consistent with Cumulus Linux conventions, and the double dash (--) to indicate the link, as required by the DOT file format.
Question 25
In Cumulus Linux, which technology enables the ability to provide active-active redundancy to servers, without the need for direct inter-switch links?
Correct Answer: C
EVPN Multi-homingenablesactive-active redundancy without inter-switch linksby usingoverlay routing over VXLAN and distributed control plane using BGP EVPN. From the officialNVIDIA Cumulus Linux EVPN Multihoming Documentation: "EVPN multihoming allows multiple Top-of-Rack (ToR) switches to connect to the same server while maintaining full layer-2 redundancy without the need for inter-switch links or traditional MLAG configuration." Key benefits: * Simplified topology (no ISL/peer-link needed) * BGP-based control plane * Fast convergence * Active-active links per host NIC Incorrect Options: * MLAGrequires ISL between switches and peer-link configuration. * VSS(Virtual Switching System) is a Cisco term, not supported in NVIDIA networking. Reference: Cumulus Linux Docs - EVPN Multihoming