Monday 19 December 2011

Difference Between Ping and Exteded Ping ? Linux Ping Command, Windows Ping command and Cisco Ping command !!

Ping command is First step of networks. Networking means to connect many devices in same or other domain. To test the connectivity we need to use this " Ping " Command. Depending on Operating system there is slight difference in using the command, but the end result is same. We need to verify the other device is alive or not and can be accessed from the network.

The full form of Ping is (Packet InterNet Groper).

Windows Ping Command

C:\>ping

Usage: ping [-t] [-a] [-n count] [-l size] [-f] [-i TTL] [-v TOS]
            [-r count] [-s count] [[-j host-list] | [-k host-list]]
            [-w timeout] target_name

Options:
    -t             Ping the specified host until stopped.
                   To see statistics and continue - type Control-Break
                   To stop - type Control-C.

    -a             Resolve addresses to hostnames.

    -n count       Number of echo requests to send ( Default 4)

   -l size        Send buffer size (The default is 32. The maximum size is 65,527)

     -f             Set Don't Fragment flag in packet.

    -i TTL         Time To Live.(For Windows XP hosts, this is typically 128. The maximum TTL is 255.

    -v TOS         Type Of Service.(The default is 0. TOS is specified as a decimal value from 0 to 255. )

    -r count       Record route for count hops ( The Count must be a minimum of 1 and a maximum of 9. )

   -s count       Timestamp for count hops.(The Count must be a minimum of 1 and a maximum of 4. )

    -j host-list   Loose source route along host-list.( The maximum number of addresses or names in the host list is 9. )
    -k host-list   Strict source route along host-list.(The maximum number of addresses or names in the host list is 9)
    -w timeout     Timeout in milliseconds to wait for each reply.(The default time-out is 4000 (4 seconds))

Linux Ping Command



[root@localhost ~]# ping
Usage: ping [-LRUbdfnqrvVaA] [-c count] [-i interval] [-w deadline]
            [-p pattern] [-s packetsize] [-t ttl] [-I interface or address]
            [-M mtu discovery hint] [-S sndbuf]
            [ -T timestamp option ] [ -Q tos ] [hop1 ...] destination
[root@localhost ~]#

OPTIONS

-a
Audible ping.
-A
Adaptive ping. Interpacket interval adapts to round-trip time, so that effectively not more than one (or more, if preload is set) unanswered probes present in the network. Minimal interval is 200msec for not super-user. On networks with low rtt this mode is essentially equivalent to flood mode.
-b
Allow pinging a broadcast address.
-B
Do not allow ping to change source address of probes. The address is bound to one selected when ping starts.
-c count
Stop after sending count ECHO_REQUEST packets. With deadline option, ping waits for count ECHO_REPLY packets, until the timeout expires.
-d
Set the SO_DEBUG option on the socket being used.
-F flow label
Allocate and set 20 bit flow label on echo request packets. (Only ping6). If value is zero, kernel allocates random flow label.
-f
Flood ping.
-i interval
Wait interval seconds between sending each packet. The default is to wait for one second between each packet normally, or not to wait in flood mode. Only super-user may set interval to values less 0.2 seconds.
-I interface address
Set source address to specified interface address. Argument may be numeric IP address or name of device. When pinging IPv6 link-local address this option is required.
-l preload
If preload is specified, ping sends that many packets not waiting for reply. Only the super-user may select preload more than 3.
-L
Suppress loopback of multicast packets. This flag only applies if the ping destination is a multicast address.
-n
Numeric output only. No attempt will be made to lookup symbolic names for host addresses.
-p pattern
You may specify up to 16 ``pad'' bytes to fill out the packet you send. This is useful for diagnosing data-dependent problems in a network. For example, -p ff will cause the sent packet to be filled with all ones.
-Q tos
Set Quality of Service -related bits in ICMP datagrams. tos can be either decimal or hex number. Traditionally (RFC1349), these have been interpreted as: 0 for reserved (currently being redefined as congestion control), 1-4 for Type of Service and 5-7 for Precedence. Possible settings for Type of Service are: minimal cost: 0x02, reliability: 0x04, throughput: 0x08, low delay: 0x10. Multiple TOS bits should not be set simultaneously. Possible settings for special Precedence range from priority (0x20) to net control (0xe0). You must be root (CAP_NET_ADMIN capability) to use Critical or higher precedence value. You cannot set bit 0x01 (reserved) unless ECN has been enabled in the kernel. In RFC2474, these fields has been redefined as 8-bit Differentiated Services (DS), consisting of: bits 0-1 of separate data (ECN will be used, here), and bits 2-7 of Differentiated Services Codepoint (DSCP).
-q
Quiet output. Nothing is displayed except the summary lines at startup time and when finished.
-R
Record route. Includes the RECORD_ROUTE option in the ECHO_REQUEST packet and displays the route buffer on returned packets. Note that the IP header is only large enough for nine such routes. Many hosts ignore or discard this option.
-r
Bypass the normal routing tables and send directly to a host on an attached interface. If the host is not on a directly-attached network, an error is returned. This option can be used to ping a local host through an interface that has no route through it provided the option -I is also used.
-s packetsize
Specifies the number of data bytes to be sent. The default is 56, which translates into 64 ICMP data bytes when combined with the 8 bytes of ICMP header data.
-S sndbuf
Set socket sndbuf. If not specified, it is selected to buffer not more than one packet.
-t ttl
Set the IP Time to Live.
-T timestamp option
Set special IP timestamp options. timestamp option may be either tsonly (only timestamps), tsandaddr (timestamps and addresses) or tsprespec host1 [host2 [host3 [host4]]] (timestamp prespecified hops).
-M hint
Select Path MTU Discovery strategy. hint may be either do (prohibit fragmentation, even local one), want (do PMTU discovery, fragment locally when packet size is large), or dont (do not set DF flag).
-U
Print full user-to-user latency (the old behaviour). Normally ping prints network round trip time, which can be different f.e. due to DNS failures.
-v
Verbose output.
-V
Show version and exit.
-w deadline
Specify a timeout, in seconds, before ping exits regardless of how many packets have been sent or received. In this case ping does not stop after count packet are sent, it waits either for deadline expire or until count probes are answered or for some error notification from network.
-W timeout
Time to wait for a response, in seconds. The option affects only timeout in absense of any responses, otherwise ping waits for two RTTs.

Cisco Extended Ping Command

Router# ping
Protocol [ip]:
Target IP address: 
Repeat count [5]: 
Datagram size [100]:
Timeout in seconds [2]:
Extended commands [n]: 
Source address or interface: 
Type of service [0]:
Set DF bit in IP header? [no]:
Validate reply data? [no]:
Data pattern [0xABCD]:
Loose, Strict, Record, Timestamp, Verbose[none]:
Sweep range of sizes [n]:



Protocol [ip]: Prompts for a supported protocol. Enter appletalk, clns, ip, novell, apollo, vines, decnet, or xns. The default is ip.

Target IP address:Prompts for the IP address or host name.The default is none.

Repeat count [5]:Number of ping packets that are sent to the destination address. The default is 5.

Datagram size [100]:Size of the ping packet (in bytes). Default: 100 bytes.

Timeout in seconds [2]:  Timeout interval. Default: 2 (seconds).

Extended commands [n]: Specifies whether or not a series of additional commands appears. The default is no.

Source address or interface: The interface or IP address of the router to use as a source address for the probes.


Type of service [0]: Specifies the Type of Service (ToS). The default is 0.

Set DF bit in IP header? [no]: Specifies whether or not the Don't Fragment (DF) bit is to be set on the ping packet. If yes is specified, the Don't Fragment option does not allow this packet to be fragmented when it has to go through a segment with a smaller maximum transmission unit (MTU), and you will receive an error message from the device that wanted to fragment the packet. The default is no.

Validate reply data? [no]: Specifies whether or not to validate the reply data. The default is no.

Data pattern [0xABCD] Specifies the data pattern. Different data patterns are used to troubleshoot framing errors and clocking problems on serial lines. The default is [0xABCD].

Loose, Strict, Record, Timestamp, Verbose[none]: IP header options. This prompt offers more than one option to be selected. They are:

    Verbose is automatically selected along with any other option.

    Record is a very useful option because it displays the address(es) of the hops (up to nine) the packet goes through.

    Loose allows you to influence the path by specifying the address(es) of the hop(s) you want the packet to go through.

    Strict is used to specify the hop(s) that you want the packet to go through, but no other hop(s) are allowed to be visited.

    Timestamp is used to measure roundtrip time to particular hosts.

The default is none.

Sweep range of sizes [n]:Allows you to vary the sizes of the echo packets that are sent. The default is no.

!!!!!   

Each exclaimation point (!) denotes receipt of a reply. A period (.) denotes that the network server timed out while waiting for a reply.

Success rate is 100 percent

Percentage of packets successfully echoed back to the router. Anything less than 80 percent is usually considered problematic.

round-trip min/avg/max = 1/2/4 ms
   
Round-trip travel time intervals for the protocol echo packets, including minimum/average/maximum (in milliseconds).


Important Points on Ping Command

1) Extended Ping works only on Cisco's platform.

2) To ping to broadcast address use Linux Ping use -b option.

3) Using Cisco Extended Ping or Linux Ping the source address can be changed.

4) Use -f option of Linux for flood ping.

5) QoS can be set using any of above ping command of OS.

6) TTL  value can be set by using Windows Ping command (- i option ) or Linux Ping command ( -t ).

7)  Linux Ping command can be used for PATH MTU discovery using option -M.

8) HostList can be given in windows ping command.

9) User-to-User Latency can be taken using Linux Ping Command -U option.

10) Timestamp for IP can be set using Linux command -T.

11) Using Linux -p command we can specify up to 16 ``pad'' bytes to fill out the packets sent.


Send me feedback/comments on embsystest@gmail.com.

"Keep Learning , Keep sharing"