What are the reasons why the Linux network card is unable to start up?

There are various reasons that may cause the Linux network card to not start up, here are some possible reasons:

1. Hardware malfunction: It could be the network card itself experiencing issues, such as problems with the physical connection or damage to the network card.
2. Driver issue: it could be a problem with the network card driver, such as an incompatible driver version or the driver not being installed correctly.
3. Configuration error: it could be due to incorrect settings in the network configuration file, such as IP address, subnet mask, gateway, etc.
4. The internet service is not started: It may be because the network service is not properly started, such as the network management service (such as NetworkManager) not running or being disabled.
5. Conflict issues: It could be conflicting with other devices or services, such as IP address conflicts or conflicts with firewall rules.
6. Software update issue: It could be caused by system upgrades or software updates, such as drivers becoming incompatible or configuration files being reset after an update.
7. Permission management issue: lack of administrator permission may prevent the network card from starting, requiring the use of sudo or root permission to start the network card.

The above are just some possible reasons, the specific problem needs to be investigated and analyzed based on the actual situation.