- tuned is a profile-based system tuning tool that uses the udev device manager to monitor connected devices, and enables both static and dynamic tuning of system settings. Packages in Debian are 'tuned' and 'tuned-utils'.
- Using netstat and dropwatch to observe packet loss on Linux servers - uses the 'dropwatch' package (needs kernel symbols).
- Track a packet as it goes through the kernel (linux)
Monday, January 20. 2020
Linux Performance
Linux Open Ports
Courtesy of 3 quick ways to reduce your attack surface on Linux, a command to identify open ports and identify the associated application:
$ ss -tulnp --no-header | awk '{print($1, $5, $7)}' udp 0.0.0.0:32770 users:(("vlc",pid=2786557,fd=39)) udp 0.0.0.0:32771 users:(("vlc",pid=2786557,fd=40)) udp 127.0.0.1:123 udp 0.0.0.0:123 udp 0.0.0.0:631 udp 0.0.0.0:37019 udp 0.0.0.0:5353 udp 0.0.0.0:39276 users:(("vlc",pid=2786557,fd=50)) udp 0.0.0.0:39277 users:(("vlc",pid=2786557,fd=51)) tcp 0.0.0.0:61209 tcp 127.0.0.1:25 tcp 127.0.0.1:5433 tcp 0.0.0.0:8794 tcp 127.0.0.1:3493 tcp 127.0.0.1:5101 users:(("ssh",pid=899751,fd=4)) tcp 127.0.0.1:5102 users:(("ssh",pid=2187130,fd=4)) tcp 127.0.0.1:5201 users:(("ssh",pid=2186389,fd=5)) tcp 127.0.0.1:5202 users:(("ssh",pid=2186389,fd=7)) tcp 0.0.0.0:22 tcp 127.0.0.1:631 tcp 127.0.0.1:5432 ...
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