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| | -E : Decrypt IPSEC traffic by providing an encryption key.</nowiki> | | -E : Decrypt IPSEC traffic by providing an encryption key.</nowiki> |
| | | | |
| | + | === 1500 bytes capture excluding port 22 === |
| | tcpdump -i eth1 -s 1500 port not 22 | | tcpdump -i eth1 -s 1500 port not 22 |
| | | | |
| − | You can skip additional ports too:
| + | === Skip ports === |
| | + | tcpdump -i eth1 -s 1500 port not 22 and port not 53 |
| | + | |
| | + | === Filter ip or hostname === |
| | + | tcpdump -i eth1 port not 22 and host 1.2.3.4 |
| | + | |
| | + | === Raw output view === |
| | + | tcpdump -ttttnnvvS |
| | + | |
| | + | === Hex output === |
| | + | tcpdump -nnvXSs 0 -c1 icmp |
| | + | |
| | + | === Filter by source or destination |
| | + | tcpdump src 2.3.4.5 |
| | + | tcpdump dst 3.4.5.6 |
| | | | |
| − | tcpdump -i eth1 -s 1500 port not 22 and port not 53 | + | === Filter by net === |
| | + | tcpdump net 1.2.3.0/24 |
| | + | |
| | + | === Filter by port === |
| | + | tcpdump port 3389 |
| | + | tcpdump src port 3389 |
| | + | |
| | + | === Filter by protocol === |
| | + | tcpdump icmp |
| | + | === Filter by packet size === |
| | + | tcpdump less 32 |
| | + | tcpdump greater 64 |
| | + | tcpdump <= 128 |
| | + | === Read/Write File === |
| | + | ==== Write ==== |
| | + | tcpdump port 80 -w capture_file |
| | + | ==== Read ==== |
| | + | tcpdump -r capture_file |
| | | | |
| − | You can also use ip or hostname:
| + | == Combinations == |
| | + | * AND |
| | + | and or && |
| | + | * OR |
| | + | or or || |
| | + | * EXCEPT |
| | + | not or ! |
| | + | === traffic from 10.5.2.3 going to any host on port 3389 === |
| | + | tcpdump -nnvvS src 10.5.2.3 and dst port 3389 |
| | + | === Traffic from one network to another === |
| | + | tcpdump -nvX src net 192.168.0.0/16 and dst net 10.0.0.0/8 or 172.16.0.0/16 |
| | + | === non icmp traffic going to a specific ip === |
| | + | tcpdump dst 192.168.0.2 and src net and not icmp |
| | | | |
| − | tcpdump -i eth1 port not 22 and host 1.2.3.4
| + | == More At == |
| | + | https://danielmiessler.com/study/tcpdump/#dns |