The Mellanox IS5023 40Gbit connection is not functioning properly.
The Mellanox IS5023 40Gbit connection is not functioning properly.
Hello! I recently purchased a large collection of servers and equipment at a very favorable price. The setup included Mellanox MHQH19B-XTR cards, essential QSFP cables, and three 18-port InfiniBand switches from Mellanox. In my experience, these switches are typically unmanaged, but they do offer manageable features. I believe they provide a WebGUI or at least a programmable I²C interface via RJ45. My issue is that when connecting Server A and Server B, both have QSFP cards installed and detected, the links function properly with cables, but linking Server A through an InfiniBand switch to Server B doesn’t work. No lights illuminate on the cards or switches, suggesting either a failure or incorrect configuration. I suspect it might be a faulty switch. I’ve tried the other two switches as well, but the same problem persists. When I connected the switches together briefly, they worked temporarily, but disconnecting them to test the second one left them nonfunctional—though sometimes the port lights appeared briefly. It’s possible these switches are programmable, yet there isn’t a visible reset option. If I were to program them, how would I do it through the RJ45 I²C connection? The proprietary cables I bought cost around $600, which is essentially just a standard RJ45 to serial, serial to I²C to USB conversion. It seems these parts aren’t available in the EU anymore.
The device’s premium design and specific use case often cause interfaces to shut down automatically by default. Likely the intention is to speed up installation, so only essential ports remain active. This behavior is typical in CISCO routers but switches are generally left unmanaged with all ports enabled until configured. It might be a partial Layer 3 switch; you’ll need to check the console for details. If it has a WebUI, locate its IP or required software. If you only need the IP address, you may have to consult the console since there’s no direct non-RJ-45 access and DHCP status isn’t clear. Even with server-rack compatibility, the back area is hard to reach—manuals are unlikely available. You’ll need a console cable and patience, as shipping delays are common. If you can’t obtain the extra adapter, consider a laptop model that includes an RS232 port on its motherboard. I’d suggest checking Ebay; prices may be higher than expected, but it’s worth it for the convenience. One option is around $4.25 with a Serial USB to RJ-45 adapter, or about $4.54 (though I’m surprised such a product exists).