How to capture packets for a long time using tcpdump in Linux

Linux with tcpdump long-term packet capture operation method command: tcpdump-ieth1-s0-wk.cap last added is to make this command in the background for long-term execution, otherwise close sshclient tcpdump command will stop on its own. Then log on to linux again and perform the following operations-bash-3.00 # ps-ef | greptcpdumppcap3660101 on Linux. TcpdumpOperation Command for capturing packets for a long time:
Tcpdump-I eth1-s 0-w k. cap &

Add the command to make it run in the background for a long time. otherwise, after the ssh client is disabled
The tcpdump command stops automatically.

Then log on to linux again and perform the following operations-bash-3.00 # ps-ef | grep tcpdump
Pcap 3660 1 0? 00:00:00 tcpdump-I eth1-s 0-wk. cap
Root 3721 3680 0 00:00:00 pts/1 grep tcpdump

-Bash-3.00 # kill 3660

-Bash-3.00 # ls-l
-Rw-r -- 1 root 33714 Mar 29 k. cap

Download the packet to the local device for analysis. Note:-s 0 indicates that the size of captured packets is not limited.
When using this command, you must pay attention to the remaining space (df-h) on the hard disk to avoid the abnormal use of the system due to excessive files.