Building TCPDump for Netkit

Netkit-JH requires a vanilla version of TCPDump (rather than the TCPDump from Debian's repositories) as Debian's TCPDump patches do not allow us to do this:

tcpdump -i eth0 -w /hostlab/eth0.pcap

Instead, we would have to do:

tcpdump -i eth0 -w /hostlab/eth0.pcap -Z root -C 1

or

tcpdump -i eth0 > /hostlab/eth0.pcap

To build TCPDump, firstly start a Netkit machine with a tap interface (this will require root privileges) and 512MB of RAM.

$ vstart netkit_tcpdump --eth0=tap,10.0.0.1,10.0.0.2 --mem=512

Once the VM has started, run the commands below to configure DNS, download build packages and compile TCPDump.

$ echo "nameserver 8.8.8.8" > /etc/resolv.conf

$ apt update && apt install git make build-essential flex bison

$ git clone https://github.com/the-tcpdump-group/tcpdump

$ git clone https://github.com/the-tcpdump-group/libpcap

$ cd libpcap

$ ./configure && make

$ cd ../tcpdump

$ ./configure && make

$ cp tcpdump /hosthome/tcpdump

$ cp tcpdump.1 /hosthome/tcpdump.1

Now move the tcpdump and tcpdump.1 files out of your home directory into the applicable directories inside netkit-jh-build/fs/filesystem-tweaks.