CompTIA Linux+ (XK0-006)TroubleshootingEasy
A system administrator is investigating a Linux server that is experiencing intermittent network connectivity issues. They suspect a problem with the network interface card (NIC) driver or hardware. Which of the following commands would best provide detailed statistics about network interface errors, such as dropped packets and collisions?
- A`ip a`
- B`ethtool -S eth0`
- C`ss -s`
- D`netstat -rn`
Show answer & explanationAnswer & explanation
Correct answer: B. `ethtool -S eth0`
`ethtool -S <interface>` provides detailed statistics specific to the network interface, including error counts like rx_dropped, tx_errors, and collisions, which are crucial for diagnosing hardware or driver issues. Other commands provide general network information but not these specific error counters.
Why the other options are wrong
- A. `ip a` shows IP addresses and interface status but not detailed error statistics.
- C. `ss -s` shows summary statistics for sockets, which is not relevant for NIC hardware errors.
- D. `netstat -rn` displays the routing table, not detailed interface error statistics.
ethtool -S
The `ethtool -S` command is used to query or control network driver and hardware settings, specifically displaying detailed statistics for a specified network interface.
- Requires root privileges to modify settings, but not to view statistics.
- Provides granular counters for receive/transmit errors, dropped packets, collisions, etc.
- Useful for diagnosing physical layer or driver issues on a network interface.
Memory trick: Errors are 'S'erious, so use 'S'tatistics from 'eth'tool.