STANDARD PING
This is the usual way to do a ping. A standard ping is used to check the availability of a host. This is the only purpose a PING should be used. This can be done from the command prompt on Windows, Linux, Unix and Cisco routers by typing the following command:
ping < ip address >
This will return a result that you must interpret.
UNABLE TO PING?
If you are unable to ping a remote machine, there are several possible causes:
- If you are trying to ping a host name, make sure the name you are pinging is fully qualified.
- If pinging the fully qualified host name does not work, try pinging the IP address of the destination machine. If ping fails when you try the name of the site, but works when you try the IP address, it's NOT a network problem, it's a problem with DNS.
- If you are trying to ping a site and both the name and the IP address fail, they may be administratively denied by an access control list. Cisco routers report !A when they are blocking ping with an access list. Try a traceroute instead, or if it is a website, try browsing it.
- If the traceroute you performed shows multiple hops between you and the destination, then try pinging each host in the path starting closest to you and working your way towards the destination until you find the host that fails to respond to ping. Use a traceroute (successfully) to get a list of the hosts between you and the destination for this purpose.
EXTENDED PING
An extended ping is often used by the less technically knowledgeable to track "packet loss" or "latency". The command to run an extended number of repeated PINGs varies by platform:
ping -s < ip address >
ping -t < ip address >
Both of the above commands result in sending out 1 ping per second until the process is halted by pressing CTRL-C.
CISCO
Here is an example of an extended ping directly from a router:
router>ping
Protocol [ip]:
Target IP address: www.inetdaemon.com
Translating 209.1.221.10
Repeat count [5]: 100
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]:
Sweep range of sizes [n]:
Type escape sequence to abort.
Sending 100, 100-byte ICMP Echos to 207.150.192.12, timeout is 2 seconds:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Success rate is 100 percent (100/100), round-trip min/avg/max = 12/19/280 ms
A Cisco router sends a fixed number of packets out as fast as it can generate them, then waits for the responses. Extended pings are best used if you must discover end-to-end packet loss or latency issues.
Running these commands will generate output you must interpret.
RECORD ROUTE PING
Use a record route ping in cases where there are few hops and you need additional host information about the routing path.
EXAMPLE: In the satellite arena where all connections are simplex, and are not always from the same provider or connected to the same interface. A record route ping can allow you to follow the satellite downlink path, and then discover the uplink path if it is unknown, thereby allowing you to perform additional pings to the uplink address to verify the return path.
Record Route PING records the IP address of each device's receiving interface in the packet. This allows you to see the complete path, provided it does not exceed 9 hops, which is the maximum that will fit in the ICMP header.