I have a rack-mounted KVM now, and it's great, but I'm working on building out a new Proxmox cluster which might not have a graphics output at all on some of the nodes. So, I need a new remote access solution for them.
The new nodes I'm planning on building will all be based on used consumer hardware, so I'm limited by what would be available on normal mATX boards. This doesn't include IPMI, and if I go with AMD-based CPUs, doesn't include an iGPU either. So I either need to get cheap GPUs to add to the second PCIe slot (which I then can't use for things like HBAs), or at least put a GPU in for troubleshooting. However, adding a GPU often moves PCIe devices, leading to issues where the network card on enp4 is now enp5 when the GPU is attahed, for example. So trouleshooting for real would be a nightmare with this approach.
But! There is an alternative. Despite being ancient, many boards still have a COM header connected to the chipset, which provides a basic serial port header ('COM1' in Windows) and is completely usable. So, my goal is to connect this COM header to a female RJ45 port on the back of the computer, so I can plug in a 'Cisco-style' terminal cable. These sorts of cables (RJ45 serial to USB) are readily available cheaply on the internet, and I can open a terminal emulator on my laptop to diagnose the worst issues that lock up the system.
Since some systems are rumored to not POST without a graphics card, I'm testing this approach today.
Link to my blog post with the wiring diagram and Proxmox setup commands:
[ Ссылка ]
Parts I used to build this:
* Female 2x5 IDC Connector (50 pack) - [ Ссылка ]
* RJ45 Panel Mount Female Extension - [ Ссылка ]
* RJ45 Console Cable to USB-A - [ Ссылка ]
* RJ45 Console Cable to USB-C - [ Ссылка ]
Feel free to chat with me more on my Discord server:
[ Ссылка ]
If you'd like to support me, feel free to here: [ Ссылка ]
Timestamps:
00:00 - Introduction
01:39 - Building the Cable
03:40 - Test System
05:12 - No-GPU Test
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#proxmox #homelab #serial
