centos check network connection (hardware)

1. View all the network cards of the current host, where, lspci: display all PCI bus devices in the system or all tools connected to the bus

 lspci|grep -i eth

2. Check the physical connection status, such as checking whether the network cable is plugged in and whether the network cable is plugged in
Note: eth0 is my own network card, check according to the actual situation

ethtool eth0

3. mii-tool eth0

4. View the local routing table

ip route

5. View Gateway

cat /etc/resolv.conf