Gentoo for Network Admins

This article hosts Article description::a guide for fellow UNIX Network Admins/SRE/DevOps into configuring a fully-fledged Swiss army knife Gentoo in order to make network debugging much easier.

DNS debugging
contains most of the DNS debugging tools such as, , and.

SSL/TLS/PKI troubleshooting
The, , commands and others:

Port knocking/scanning
Most popular command for is

Check which ports are open, which services are running with.

Traffic analyzers
Listen on an interface and show src/dest traffic and speed:

Inspect incoming/outgoing packets:

Network bandwidth measurement
has many use cases. It can for example stress test a network by running

IP troubleshooting (L3)
does a traceroute by probing with ICMP packets:

In case ICMP is blocked by some firewall on the LAN, try :

Layer four traceroute, traceroute using TCP:

L1 troubleshooting
Link detection, WOL support, link modes et. al.:

Directly connected neighbor detection, capabilities, connected port etc:

Others
Copy logs, file contents, et. al. without leaving terminal

External resources

 * Tcpdump examples: 50 practical recipes for everyday tasks
 * Julia Evans tcpdump interactive magazine
 * Find RFC's easier