Checking the network card and optical module in Linux system

You can check network card and optical module details in Linux using commands like ip, ethtool, lshw, and nmcli to view interface status, MAC addresses, IPs, and transceiver information.

Listing Network Interfaces

To identify all network interfaces on your system:

• ip addr: Shows all interfaces, their IP addresses, MAC addresses, and status (UP/DOWN) .
• ifconfig: Older utility to display interface details, including IP and MAC addresses .
• ls /sys/class/net/: Lists interface names like eth0, wlan0, or enp3s0 .
• nmcli device status: Provides a summary of interfaces managed by NetworkManager, including type and connection status .

Checking Network Card Hardware

To get detailed hardware information:

• lspci: Lists all PCI devices, including network cards .
• lshw -class network: Displays detailed NIC information such as vendor, product, driver, speed, and link status .
• hwinfo --network: Provides hardware probing for network cards (may require installation) .
• dmidecode: Retrieves BIOS-level hardware information, including NICs .

Checking Link Status and Configuration

• ethtool <interface>: Shows link status, speed, duplex, auto-negotiation, and transceiver type for Ethernet and fiber interfaces. For example, ethtool eth0 displays whether the link is detected, speed (e.g., 10Gb/s), and transceiver details (internal or SFP module) .
• ip link show <interface>: Displays interface state (UP/DOWN) and MAC address .
• netstat -i: Lists interfaces with packet and byte statistics .

Checking Optical Transceivers

For fiber network cards with SFP or QSFP modules:

• Use ethtool -m <interface> to read transceiver information such as vendor, serial number, wavelength, and supported speeds .
• Ensure the interface is active (Link detected: yes) to retrieve accurate transceiver data .

Summary

1. Identify interfaces: ip addr, ifconfig, ls /sys/class/net/
2. Check hardware: lspci, lshw -class network, hwinfo, dmidecode
3. Check link and configuration: ethtool <interface>, ip link show <interface>, netstat -i
4. Inspect optical modules: ethtool -m <interface> for SFP/QSFP transceivers Using these commands, you can fully inspect your network cards, verify connectivity, and obtain detailed optical module information on a Linux system.