More on Networking
This document help to undersand basic Network Configuration for a machine and general networking.
ifconfig - IP address
To check your own IP address.
ifconfig
In the example below: LAN Ethernet IP is: 192.168.0.11 Mac Address is: 00:16:35:69:BD:79
Example Output:
$ ifconfig
eth0 Link encap:Ethernet HWaddr 00:16:35:69:BD:79
inet addr:192.168.0.11 Bcast:192.168.0.255 Mask:255.255.255.0
inet6 addr: fe80::212:ff35:fe69:bd12/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:16791460 errors:0 dropped:0 overruns:0 frame:0
TX packets:30066639 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2182259898 (2.0 GiB) TX bytes:3951206845 (3.6 GiB)
Interrupt:209 Memory:fdef0000-fdf00000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:32098 errors:0 dropped:0 overruns:0 frame:0
TX packets:32098 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:3227365 (3.0 MiB) TX bytes:3227365 (3.0 MiB)
ping - Check network Access
ping [HOST or IP-ADDRESS or WEBSITE]
netstat - Network Activity
netstat -r
Example Output:
$ netstat -r
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
192.168.0.0 * 255.255.255.0 U 0 0 0 eth0
169.254.0.0 * 255.255.0.0 U 0 0 0 eth0
10.1.0.0 192.168.0.2 255.255.0.0 U 0 0 0 eth0
default 192.168.0.1 0.0.0.0 UG 0 0 0 eth0
Other usage
$ netstat -a | grep LISTEN | grep -v LISTENING
tcp 0 0 localhost.localdomain:32000 *:* LISTEN
tcp 0 0 localhost.locald:bootserver *:* LISTEN
tcp 0 0 *:cbt *:* LISTEN
tcp 0 0 *:38821 *:* LISTEN
tcp 0 0 *:8009 *:* LISTEN
$ netstat -an | more
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 127.0.0.1:32000 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:2016 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:7777 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:38821 0.0.0.0:* LISTEN
traceroute - Trace server routes to remote host
This command will display the route taken to reach the remote host and, along with the stops it makes, provide some timing information that shows how long each leg in the route is taking.
traceroute [HOSTNAME or SERVER or WEBSITE]
Example output:
$ traceroute www.google.com
traceroute to www.google.com (216.58.219.4), 30 hops max, 60 byte packets
1 testwifi.here (192.168.86.1) 0.588 ms 1.110 ms 0.725 ms
2 96.120.88.245 (96.120.88.245) 9.233 ms 14.729 ms 15.564 ms
3 be-20002-rur02.santaclara.ca.sfba.comcast.net (68.85.103.169) 16.102 ms 16.221 ms 15.741 ms
4 162.151.78.129 (162.151.78.129) 15.626 ms 15.836 ms 15.772 ms
5 be-232-rar01.santaclara.ca.sfba.comcast.net (162.151.78.253) 16.099 ms * *
6 be-299-ar01.santaclara.ca.sfba.comcast.net (68.86.143.93) 15.896 ms 13.372 ms 13.345 ms
7 96.112.146.18 (96.112.146.18) 13.998 ms 96.112.146.26 (96.112.146.26) 11.898 ms 11.132 ms
8 * * *
9 108.170.236.62 (108.170.236.62) 19.286 ms 209.85.251.4 (209.85.251.4) 17.231 ms 108.170.236.60 (108.170.236.60) 16.081 ms
10 108.170.242.254 (108.170.242.254) 18.317 ms 108.170.242.238 (108.170.242.238) 17.908 ms 108.170.242.253 (108.170.242.253) 17.933 ms
11 216.239.62.41 (216.239.62.41) 18.089 ms 72.14.237.147 (72.14.237.147) 18.223 ms 66.249.94.29 (66.249.94.29) 18.394 ms
12 66.249.95.15 (66.249.95.15) 23.803 ms 216.239.54.22 (216.239.54.22) 21.822 ms 64.233.174.206 (64.233.174.206) 36.001 ms
13 108.170.234.40 (108.170.234.40) 22.110 ms 108.170.230.134 (108.170.230.134) 22.006 ms 21.297 ms
14 108.170.247.193 (108.170.247.193) 22.033 ms 21.847 ms 108.170.247.225 (108.170.247.225) 19.486 ms
15 108.170.237.143 (108.170.237.143) 20.839 ms 19.894 ms 17.991 ms
16 lax17s03-in-f4.1e100.net (216.58.219.4) 17.176 ms 17.725 ms 24.966 ms