PING Command

Purpose

Use the PING command to send an echo request to a foreign node to determine if the node is accessible. PING uses ICMP as its underlying protocol.

Operands

host_name

Specifies the foreign host to which you want to send the echo request. If you omit the host_name, the system prompts you for a host name. The host name is either a character-string name or the internet address in the standard format of the foreign host (dotted-decimal format for IPv4 addresses, and either full or compressed format for IPv6 addresses).

Help

?

Provides help information about the PING command. You cannot place the HELP parameter on the PING command line with other parameters.

Length bytes

Sets the number of bytes of the echo request. If you do not specify the operand, the default is 256. The number of bytes must be between 8 and the maximum value determined by large envelope size (lrg_env_size). For more information about large_env_size, see z/VM: TCP/IP Planning and Customization.

Count echo

Sets the number of echo requests that are sent to the foreign host. If you do not specify the operand, the default is 1. The number echo must be between 1 and 2³¹ -1 (2 147 483 647). If echo is 0, the PING command sends echo requests continually.

Timeout seconds

Sets the number of seconds that the PING command waits for a response. If you do not specify the operand, the default is 10. The number for seconds must be between 1 and 100.

ADDRTYPE IPV4

Indicates that PING is to attempt to resolve the specified host name to an IPv4 type address. If the ADDRTYPE option is not specified, PING will attempt to determine the address type to which the host name should be resolved based on a LINK option being specified, or on a SOURCEIP option being specified. If none of these options are specified, PING will first try to resolve the host name to an IPv6 address, and, if unsuccessful, it will attempt to resolve it to an IPv4 address.

ADDRTYPE IPV6

Indicates that PING is to attempt to resolve the specified host name to an IPv6 type address. If the ADDRTYPE option is not specified, PING will attempt to determine the address type to which the host name should be resolved based on a LINK option being specified, or on a SOURCEIP option being specified. If none of these options are specified, PING will first try to resolve the host name to an IPv6 address, and, if unsuccessful, it will attempt to resolve it to an IPv4 address.

LINK linkname

Allows you to specify which link to send the packet out on. The LINK parameter is valid for pinging IPv6 targets only.

If the LINK option is not specified, the link to be used is determined from the routing table. When issuing PING to a link-local address, the LINK option must be specified or the PING will fail. This is due to the fact that all IPv6 link-local addresses have the same prefix (FE80::Interface_ID), so, depending on how the Interface_ID is generated, hosts on different links could have the same link-local address.

SOURCEIP srcipaddr

Allows you to specify the source IP address that is placed in the IP header when the packet is sent out. This is needed because IPv6 can have multiple IP addresses (link-local, site-local, and global) associated with a single link, and you need to verify that the PING is returned to a specific address. If the SOURCEIP option is not specified, it is determined from the home list.

DEBUG

Displays more detailed information about the packets being sent and received by the PING program.

Usage Notes

1. More than one option can be placed on the PING command line; however, the HELP parameter is an exception and cannot be placed on the PING command line with other parameters.
2. You can enter an optional parameter multiple times, but only the last instance is used.
   Example: In the following example, LENGTH is used twice, which is valid, but the program uses the last one (LENGTH 1000):

   ping 9.60.67.166 ( LENGTH 900 LENGTH 1000

3. When the TCP/IP stack is configured to use equal-cost multipath support, and there are multiple equal-cost paths to the destination being pinged, the ping results may seem inconsistent because the echo requests will be sent out through different interfaces. In the example below, If you ping 10.2.1.3 twice (or once with a COUNT 2 specified), the first echo request will be sent out through LINK1, and the second echo request will be sent out through LINK2.

   GATEWAY
   10.2.1.3     =     LINK1     4000     HOST
   10.2.1.3     =     LINK2     4000     HOST

4. PING does not support CMS subset mode.
5. If you issue HX while PING is running, the only valid command at the VM READ is BEGIN. Any other CMS command issued will be treated as if it is the BEGIN command. You will only see the Ready; message.

Return codes

0

Command Successful.

4

One or more of the PING attempts timed out.

8

A communication error between PING and the TCP/IP stack occurred.

16

Socket Error.

100

A PING command was issued with invalid syntax.