Network

• you want an introduction to networking
• you want to know about network addressing like 10.20.64.111/24
• you want a list of networking commands
• you want to do network troubleshooting
• you want to learn how to connect to the net

Networking topics

• fake MAC address

ifconfig eth0 hw ether xx:xx:xx:xx:xx:xx

• Show all server sockets that are listening

lsof -i

• Show all connections

netstat -putan

• listen on a specific port

ngrep -qd lo port 21

• create WLAN traffic

aireplay -3 -b <MACofAP> -h <MACtoFake> -x 600 eth1

• slow down port 1234

tc qdisc  add dev eth0 root handle 1: cbq avpkt 1000 bandwidth 10mbit
tc class  add dev eth0 parent 1: classid 1:1 cbq rate 8kbit allot 1500 prio 5 bounded isolated
tc filter add dev eth0 parent 1: protocol ip prio 16 u32 match ip sport 1234 0xffff flowid 1:1
tc qdisc  add dev eth0 parent 1:1 sfq perturb 10

• find out if TOE is switched on

# ethtool --show-offload eth2
Offload parameters for eth2:
rx-checksumming: on
tx-checksumming: on
scatter-gather: on
tcp-segmentation-offload: on
udp-fragmentation-offload: off
generic-segmentation-offload: on
generic-receive-offload: on
large-receive-offload: on