Local host tables
By default, resolver first attempts to use any configured domain
name servers for resolution requests. If the resolution request cannot
be satisfied, local host tables are used. Resolver behavior is controlled
TCPIP.DATA resolver statements define if and
how domain name servers are to be used. The
LOOKUP TCPIP.DATA statement
can also be used to control how domain name servers and local host
tables are used. For more information on TCPIP.DATA statements, refer
to Communications Server: IP Configuration Reference (SC31-8776).
The resolver uses the Ipv4-unique search order for sitename information unconditionally for getnetbyname API calls. The Ipv4-unique search order for sitename information is the following. The search ends at the first file being found:
- The value of the environment variable X_SITE
The value of the environment variable is the name of the HOSTS.SITEINFO information file created by the TSO MAKESITE command.
- The value of the environment variable X_ADDR
The value of the environment variable is the name of the HOSTS.ADDRINFO information file created by the TSO MAKESITE command.
useridis the user ID that is associated with the current security environment (address space or task/thread).
jobnameis the name specified on the JOB JCL statement for batch jobs or the procedure name for a started procedure.
hlqrepresents the value of the
DATASETPREFIXstatement specified in the base resolver configuration file (if found); otherwise,
hlqis TCPIP by default.