Step‑by‑Step Guide to Inspect All Linux Server System and Hardware Details

1. System and kernel version

Run cat /etc/os-release to view distribution fields such as PRETTY_NAME (e.g., "Ubuntu 22.04.3 LTS"), VERSION_ID ("22.04"), and ID ("ubuntu", "centos", "debian"). The hostnamectl command prints a comprehensive overview including static hostname, operating system, kernel version and architecture.

Execute uname -a for a full kernel line, e.g., "Linux web-server 5.15.0-91-generic #101-Ubuntu SMP x86_64 GNU/Linux". Use uname -r to display only the version number, e.g., "5.15.0-91-generic".

2. CPU information

The lscpu command aggregates CPU data. Key fields are: Architecture: e.g., x86_64 CPU(s): number of logical CPUs (including hyper‑threads) Thread(s) per core: threads per core (2 indicates hyper‑threading) Core(s) per socket: physical cores per socket Socket(s): number of CPU sockets Model name: human‑readable CPU model CPU MHz: current operating frequency Cache L3: size of the L3 cache

Quickly obtain the logical CPU count with nproc. The model name can be shown by cat /proc/cpuinfo | grep 'model name' | head -1.

Real‑time usage is visible with top or the more colorful htop.

3. Memory information

Use free -h to see memory usage. Columns: total: physical memory total used: memory in use (including cache and buffers) free: completely unused memory shared: memory used by tmpfs buff/cache: memory used for buffers and cache available: memory truly available to applications (preferred metric for pressure assessment)

For detailed metrics, run cat /proc/meminfo, which includes MemTotal, MemFree, MemAvailable, Buffers, Cached, SwapTotal, etc.

Physical DIMM sizes are listed with sudo dmidecode -t memory | grep Size, e.g., "Size: 16384 MB" for a 16 GB module.

4. Disk information

Disk usage: df -h shows Filesystem, Size, Used, Avail, Use% and Mounted on.

Block device hierarchy: lsblk displays a tree of disks (e.g., sda) and partitions (e.g., sda1) with mount points.

Physical disk capacity: sudo fdisk -l | grep Disk prints lines such as "Disk /dev/sda: 500 GiB".

I/O performance monitoring requires the sysstat package. Run iostat -x 1 3; a %util value near 100 % indicates an I/O bottleneck.

5. Network interface information

Preferred command: ip addr. Output includes interface name (e.g., eth0), MAC address, IPv4, IPv6 and state (UP/DOWN). Specific NIC details: ip addr show eth0.

Link speed and duplex: sudo ethtool eth0 reports Speed, Duplex and Auto‑negotiation. A quick numeric speed is available via cat /sys/class/net/eth0/speed (e.g., 1000 for 1 Gbps).

Traffic statistics: cat /proc/net/dev or sar -n DEV 1 5 display per‑interface receive (rxKB/s) and transmit (txKB/s) rates.

6. Detecting physical vs. virtual machine

Simple detection: systemd-detect-virt. Return values: none: physical machine kvm, vmware, microsoft, xen, oracle: corresponding hypervisors

Detailed DMI check: sudo dmidecode -s system-product-name. Physical servers show vendor models such as "PowerEdge R740" or "ProLiant DL380"; virtual machines show generic strings like "VMware Virtual Platform" or "OpenStack Nova".

Additional hardware clues:

Disk identifiers: ls /dev/disk/by-id/. Physical disks display vendor/model names (e.g., ata‑HGST_HUS724040ALE640); virtual disks appear as virtio or scsi.

CPU feature list: compare /proc/cpuinfo between known physical and virtual hosts; VMs often lack certain flags.

Baseboard info: sudo dmidecode -t baseboard. Physical machines list specific manufacturers and models; virtual machines show generic identifiers such as "Intel Corporation 440BX Desktop Reference Platform".