Update cheatsheets

tcpdump

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+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# tcpdump
+
+> Dump traffic on a network.
+> More information: <https://www.tcpdump.org>.
+
+- List available network interfaces:
+
+`tcpdump -D`
+
+- Capture the traffic of a specific interface:
+
+`tcpdump -i {{eth0}}`
+
+- Capture all TCP traffic showing contents (ASCII) in console:
+
+`tcpdump -A tcp`
+
+- Capture the traffic from or to a host:
+
+`tcpdump host {{www.example.com}}`
+
+- Capture the traffic from a specific interface, source, destination and destination port:
+
+`tcpdump -i {{eth0}} src {{192.168.1.1}} and dst {{192.168.1.2}} and dst port {{80}}`
+
+- Capture the traffic of a network:
+
+`tcpdump net {{192.168.1.0/24}}`
+
+- Capture all traffic except traffic over port 22 and save to a dump file:
+
+`tcpdump -w {{dumpfile.pcap}} port not {{22}}`
+
+- Read from a given dump file:
+
+`tcpdump -r {{dumpfile.pcap}}`