IBM SC41-5420-04 manual Tips for Merging Host Tables, Merging TCP/IP Host Tables

A complete description of the *NIC format is found in Request for Comment (RFC) 952, Internet Host Table Specification. See the RFC Editor Site (http://www.rfc- editor.org/rfc.html) to retrieve this RFC. The subset supported on the server is shown in Table 5. The *NIC continuation characters are not supported because the record length of the file can be up to 512 bytes.

Table 5. *NIC Subset Supported on the AS400 System

Delimiter	Meaning
; (semicolon)1	Indicates the beginning of a comment. The text
	following the semicolon is a comment and is not part of
	the host table.
NET2	A keyword introducing a network entry.
GATEWAY	A keyword introducing a gateway entry.
HOST	A keyword introducing a host entry.
: (colon)	A field delimiter.
:: (two colons)	Indicates a null field.
, (comma)	A data element delimiter.

Notes:

1. If any line in the *NIC table contains a semicolon as the first column value, then that line is not merged into the server host table.

2. These entries are not merged into the server host table.

Host Table Information with *AS400 Files

The *AS400 file format is the format of the local server host table file used by iSeries TCP/IP directly. The name of the file is QATOCHOST with member HOSTS in library QUSRSYS. A single record contains an Internet address, up to four host/domain names and a text description field. For more details regarding record and file formats, use the DSPFFD (Display File Field Description) command.

This file can be exchanged between iSeries servers. However, there is no function to convert from *AS400 to *AIX or *NIC format.

Tips for Merging Host Tables

A maximum of four host names per IP address is allowed when host tables are merged. For example, if the local host table already has three host names and the physical file member to be merged has two additional host names, only the first host name in the physical file is merged into the final host table.

Host names that exist for the same Internet address are not duplicated. If the same host name is found for Internet addresses that are different, then that host name is accepted, but a warning message is displayed.

The original copy of the local host table is not saved by the MRGTCPHT (Merge TCP/IP Host Table) command. To save the original host table, create a copy of the file QUSRSYS/QATOCHOST.HOSTS by using the Copy File (CPYF) command. Do this before issuing the MRGTCPHT command.

Merging TCP/IP Host Tables

You can use imported host tables in two ways:

vOverwrite the current host table. To do this, specify Replace Host Table (*Yes) on the Merge Host Table display.

52OS/400 TCP/IP Configuration and Reference V5R1