View and set CentOS Nic status

The problem of checking and setting the CentOS Nic status accidentally found that the connection speed of the LAN of a server used for storage in the lab was only 100 MB, however, the lab uses a Gigabit Switch server as well as a gigabit Nic, And the LAN speed of other servers of the same type has reached a gigabit speed. Therefore, a problem arises: how to view the NIC device of the server, how can I adjust the current connection speed? There are already a lot of network adapters in related documents, so I don't want to worry about it. Here are some articles for your reference: the server network adapter information in the solution process is as follows. here we can see that the network adapter supports Gbit/s, however, the actual connection speed is only MB. As a storage server, this is a big loss. [Plain] [root @ store3 ~] # Ethtool eth0 Settings for eth0: Supported ports: [TP] Supported link modes: 10 baseT/Half 10 baseT/Full 100 baseT/Half 100 baseT/Full 1000 baseT/Full Supports auto-negotiation: Yes Advertised link modes: 10 baseT/Half 10 baseT/Full 100 baseT/Half 100 baseT/Full 1000 baseT/Full Advertised pause frame use: No Advertised auto-negotiation: Yes Speed: 100 Mb/s Duplex: full Port: Twisted Pair PHYAD: 1 Transceiv Er: internal Auto-negotiation: on MDI-X: Unknown Supports Wake-on: g Link detected: yes Here I mainly use ethtool for settings, however, after the setting is complete, the speed does not change [plain] [root @ store3 ~] # Ethtool-s eth0 speed 1000 [root @ store3 ~] # Ethtool eth0 Settings for eth0: Supported ports: [TP] Supported link modes: 10 baseT/Half 10 baseT/Full 100 baseT/Half 100 baseT/Full 1000 baseT/Full Supports auto-negotiation: Yes Advertised link modes: 10 baseT/Half 10 baseT/Full 100 baseT/Half 100 baseT/Full 1000 baseT/Full Advertised pause frame use: No Advertised auto-negotiation: Yes Speed: 100 Mb/s Duplex: full Port: Twisted Pair PHYAD: 1 Transceiv Er: internal Auto-negotiation: on MDI-X: Unknown Supports Wake-on: g Link detected: yes use the ethtool-s eth0 duplex full autoneg off speed 1000 command to report a parameter error, after multiple tossing times, you can find that after using ethtool-s eth0 autoeng off, you can set the network speed to 10 or 100 by using the ethtool-s eth0 speed N command, but the parameter error is reported when you change to 1000. After several attempts, I finally found a problem with the network cable !!! After changing the network speed, it will go up, speechless. Although the final problem lies in the network cable, at least I learned how to view the network card status and simple settings. It is worth record.