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(Redirected from Network)

Here are the articles that deal with networking:

Network hints

  • find out if you are connected to the internet:
  • find all computers in the subnet
nmap -sP
  • test mtu:
ping -Mdo -s 8972
  • show all connections:
netstat -putan
  • show all server sockets that are listening:
lsof -i
  • 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
  • fake MAC address
ifconfig eth0 hw ether xx:xx:xx:xx:xx:xx
  • 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

Network tools