Release Notes

5.19 Before You Begin/Determine Hostname

You must determine the names of each of your DB2 servers and Data Links servers. You will need to know these hostnames to verify the installation. When connecting to a DB2 Data Links File Manager, the DB2 UDB server internally sends the following information to the DLFM:

• Database name
• Instance name
• Hostname

The DLFM then compares this information with its internal tables to determine whether the connection should be allowed. It will allow the connection only if this combination of database name, instance name, and hostname has been registered with it, using the dlfm add_db command. The hostname that is used in the dlfm add_db command must exactly match the hostname that is internally sent by the DB2 UDB server.

Use the exact hostname that is obtained as follows:

1. Enter the hostname command on your DB2 server. For example, this command might return db2server.
2. Depending on your platform, do one of the following:
   • On AIX, enter the host db2server command, where db2server is the name obtained in the previous step. This command should return output similar to the following:

        db2server.services.com is 9.11.302.341,  Aliases:  db2server 
     

   • On Windows NT, enter the nslookup db2server command, where db2server is the name obtained in the previous step. This command should return output similar to the following:

        Server: dnsserv.services.com
        Address: 9.21.14.135
        Name: db2server.services.com
        Address: 9.21.51.178 
     

   • On Solaris, enter cat /etc/hosts | grep 'hostname'. This should return output similar to the following if the hostname is specified without a domain name in /etc/hosts:

     9.112.98.167 db2server loghost
     

     If the hostname is specified with a domain name, the command returns output similar to the following:

     9.112.98.167 db2server.services.com loghost
     

Use db2server.services.com for the hostname when registering a DB2 UDB database using the dlfm add_db command. The DB2 server's internal connections to the DLFM will fail if any other aliases are used in the dlfm add_db command.

A Data Links server is registered to a DB2 database using the DB2 "add datalinks manager for database database_alias using node hostname port port_number" command.

The hostname is the name of the Data Links server. Any valid alias of the Data Links server can be used in this command. DATALINK values that are references to this Data Links server must specify the hostname in the URL value; that is, the exact name that was used in the "add datalinks manager" command must be used when assigining URL values to DATALINK columns. Using a different alias will cause the SQL statement to fail.