What command sequence is used to identify the exact name of the server that runs as the master SM in a multi-node fabric?

To identify the server acting as the master Subnet Manager (SM), a two-step process is typically used. First, the sminfo command is run on any node in the fabric. This command queries the active SM and returns its details, including the master SM's Port GUID. Second, the ibnetdiscover command is used to generate a complete topology of the fabric, which lists all nodes, their hostnames (if available), and their associated Port GUIDs. By cross-referencing the Port GUID from sminfo with the output of ibnetdiscover, the exact server name can be identified.

B. The ibstat command displays the status of the local InfiniBand adapter (HCA) on the machine where it is run, not fabric-wide master SM information.

C. The ibhosts command displays a list of hosts discovered in the fabric, similar to ibnetdiscover, but does not specifically identify the master SM.

D. The ibswitches command lists all the switches discovered in the fabric topology, not the node running the master SM service.

1. Linux man-pages project. (2021). sminfo(8) — Linux manual page. "sminfo queries the SM/SA for SM information." It returns the SMInfo: Port GUID of the master.

2. Linux man-pages project. (2021). ibnetdiscover(8) — Linux manual page. "ibnetdiscover performs a network discovery and outputs a human readable topology file." The output maps node names to GUIDs.

3. NVIDIA Corporation. (2023). NVIDIA Mellanox OFED for Linux User Manual (Rev 23.10). Section 7.1.1, "ibnetdiscover," p. 289. Describes how the tool discovers and reports topology.