HOSTS statement

Use the HOSTS statement in the Name Service Switch (NSSwitch) configuration file to specify the order in which the DNS or local files are to be used for host name resolution for IBM® z/OS® Container Platform environments.

Note: The z/OS UNIX file /etc/nsswitch.conf in the container’s filesystem namespace (if it exists), is used as the NSSwitch configuration file.

Syntax

Parameters

DNS: The domain name servers specified by the NAMESERVER statement is used for name resolution. The NAMESERVER statement can be specified in the z/OS UNIX file /etc/resolv.conf in the container’s filesystem namespace. For more information, see NAMESERVER statement.
FILES: The local host file, /etc/hosts in the container’s filesystem namespace (if it exists), is used for name resolution.

Steps for modifying

You can refresh this statement using the MODIFY RESOLVER,REFRESH command. For more information about parameters used with the MODIFY command, see z/OS Communications Server: IP System Administrator's Commands.

Examples

In the following example, only the name servers are queried directly:

hosts: DNS

In the following example, only the local host tables are used:

hosts: FILES

In the following example, the local host tables are used first. If there is no resolution, then the name servers are queried directly.

hosts: FILES DNS

In the following example, the name servers are queried directly. If there is no resolution, then the local host tables are used next.

hosts: DNS FILES

Usage notes

If a HOSTS statement is not specified, the domain name servers are queried first, and if the resolution request is not successful, the local host file, if it exists, is used.
If an incorrect parameter value is specified, the entire HOSTS statement is ignored.
The last syntactically correct HOSTS statement is used.