lnstat

Additional Notes

lnstat displays Linux kernel network statistics from various subsystems, including routing cache, neighbor cache (ARP), and network statistics. It reads data from /proc/net/stat/ and presents it in a configurable table format.

It is useful for monitoring network performance, debugging routing issues, and tracking neighbor discovery activity. Unlike netstat -s, lnstat can show real-time updates at configurable intervals, making it suitable for continuous monitoring.

Syntax

lnstat [options]

Parameters

• options: Flags that change how lnstat behaves.
• target: Optional file, device, interface, user, service, or command target when the command supports one.

Common Options

• -h: Show help message.
• -V: Show version information.
• -c count: Print statistics count times then exit.
• -d delay: Update interval in seconds (can be fractional, e.g., 0.5).
• -s subject: Set the statistics subject (arp_cache, rt_cache, rt_stat, or net_stat).
• -i mod: Select fields of each statistic.
• -w width: Set field width for each statistic.

Examples

lnstat

Show all network statistics, updating every second.

lnstat -s rt_cache -c 5

Show routing cache statistics 5 times and exit.

lnstat -s arp_cache -d 2

Show ARP cache statistics, updating every 2 seconds.

lnstat -s net_stat -i 1,2,3 -w 10

Show net statistics with only the first 3 fields, each 10 characters wide.

Practical Notes

• lnstat reads from /proc/net/stat/ files, which must be available and readable.
• Each kernel subsystem exposes different fields; use lnstat --help or check the relevant /proc file to see available fields.
• For one-shot statistics, use cat /proc/net/stat/<subsystem> directly.