ping {name|IP number}

See : https://en.wikipedia.org/wiki/Ping_(networking_utility)

See : http://www.thegeekstuff.com/2009/11/ping-tutorial-13-effective-ping-command-examples/ ping does repeated pings. When successful, it reports back :

• the name.
• the IP.
• ping try.
• ttl count (how many routing nodes traversed).
• time taken to respond.

Some errors :

• TTL Expired in Transit - exceeded defined number of hops.
  -i will allow you to increase up to 255.
• Destination Host Unreachable - host not responding, possibly down.
• Unknown Host - host does not exist, not valid name.
• Request Timed Out - did not get a reply.
  Some systems won't resond to ping.
  Heavy network traffic delayed pat TTL
  Router errors
  Use -w option to prevent extended hangs.
  

-c # - count, set a specific number pings to do.
-i # - interval. Default 1/sec. Only super user can do quicker.
-q - print only summary of pings, used with -c
-n - don't bother with printing DNS name.
-R - show route of ping.
-w - sets maximum time to run ping.

Lists IP or DNS id
HWtype. e.g ether
HWaddress, i.e mac#
Flags
Iface, some systems may have more than one interface.

Some options :

• -v - verbose.
• -n - list IP even if DNS name available.
• -i - pick secondary interface.
• -d - delete entry from lookup table (super user).
• -s - add entry to lookup table (super user).

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• dig

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• nslookup - queries name server for IP. Do a DNS resolution at the prompt.

  nslookup eval.cs.niu.edu

  nslookup - interactive mode.

  Some command line options :

  • -debug - returns ID of DNS server resolving, IP, and names.
  • -type=soa domain - source of authority. Useful with more generic name.
    
  • -type=ns domain - source of authority. Useful with more generic name.
    
  • -type=any domain - available info. Useful with more generic name.
    nslookup -query=any niu.edu

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• ifconfig - list systems network configuration.

  Provides :

  • card interface ID
  • HWaddr - mac@
  • IPv4 address
  • Broadcast address
  • IPv6 address
  • Count of packets sent and received and success/failure counts.
  This will list at least one valid network interface and lo, loopback. If multiple network cards exist, they will be listed. If you are running a virtual system enviroment, this will also have an 'interface' id.

  Some command line options :

  • -a - list all interfaces, even those down.
  • -s - short list. Lists interface ID and traffic count.
  • -v - verbose. Fill out some error reporting.

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  whois

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  netstat - network statistics. Lists connections (sockets), routing tables, network interface info, and protocol statistics.

  Useful for trouble shooting.

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  nmap