Difference between revisions of "Networking"

From Linuxintro
imported>ThorstenStaerk
 
(10 intermediate revisions by 4 users not shown)
Line 5: Line 5:
 
* [[set up Network Address Translation]]
 
* [[set up Network Address Translation]]
 
* [[teaming your network cards]]
 
* [[teaming your network cards]]
* [[routing]]
 
 
* [[set up a firewall]]
 
* [[set up a firewall]]
 
* [[networking commands]]
 
* [[networking commands]]
 
* [[network troubleshooting]]
 
* [[network troubleshooting]]
 
* [[network sniffing]]
 
* [[network sniffing]]
 +
 +
= Network hints =
 +
* find out if you are connected to the internet:
 +
ping <abbr title="google's name server">8.8.8.8</abbr>
 +
* find all computers in the subnet
 +
nmap -sP <abbr title="subnet">192.168.178.0/24</abbr>
 
* test mtu:
 
* test mtu:
  ping -f -l 1500 www.mit.edu (1364)
+
  ping -Mdo -s <abbr title="test if packets of 9000 byte (incl. overhead) are possible">8972</abbr> <abbr title="the peer you want to test communication with">192.168.178.1</abbr>
 
* show all connections:
 
* show all connections:
 
  [[netstat]] -putan
 
  [[netstat]] -putan
Line 41: Line 46:
 
  tc filter add dev eth0 parent 1: protocol ip prio 16 u32 match ip sport 1234 0xffff flowid 1:1
 
  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
 
  tc qdisc  add dev eth0 parent 1:1 sfq perturb 10
 +
 +
= Network tools =
 +
* [[TCPDump]]
 +
* [[netStat]]
 +
* [[ping]]
 +
* [[ipTraf]]
 +
* [[nMap]]
  
 
= Services =
 
= Services =
 
* [[set up a web server]]
 
* [[set up a web server]]
 
* [[control a Computer via the network]]
 
* [[control a Computer via the network]]

Latest revision as of 10:49, 1 January 2021

Here are the articles that deal with networking:

Network hints

  • find out if you are connected to the internet:
ping 8.8.8.8
  • find all computers in the subnet
nmap -sP 192.168.178.0/24
  • test mtu:
ping -Mdo -s 8972 192.168.178.1
  • 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

Services