Linux System Information and Device Management: /proc/interrupts, /proc/ioports, /proc/dma, lspci, and /dev/sd?

Below gives information about interrupts like keyboard, processes etc by each cpu.

$ cat /proc/interrupts

Hardware info

$ cat /proc/ioports

$ cat /proc/dma (Direct memory access)

Connecting devices on Linux machines.

$ lspci

$ lspci -t (gives tree structure, example if vm is used it will give an idea of its related hardware)

Disk devices.

$ ls /dev/sd?

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