Converting to DNS on the 9076 SP


Contents

About this document
Procedure

About this document

This document discusses the steps of converting a Domain Name Service. It is applicable to AIX Versions 4.1.3 and beyond and PSSP 2.1 and beyond.

Procedure

This procedure applies when you are converting to a Domain Name Service (DNS) type of name resolution when /etc/hosts was previously used and the form of the /etc/hosts file was [IP address] [short host name]. Examples of this form are:
           9.19.174.50 spcntl
           9.19.174.1 spsn1
NOTE: If the /etc/hosts file was previously [IP address] [long host name] [short host name] and the new DNS domain was in the [long host name] form, the conversion to DNS on the SP is transparent and you do not need to perform the following steps.

If DNS is being implemented, change your /etc/hosts file so that if name resolution falls through to /etc/hosts from DNS, it will still be able to resolve the fully qualified domain name. Change your /etc/hosts file to look like the following example:

           9.19.174.50 spcntl.aix.dfw.ibm.com spcntl
           9.19.174.1 spsn1.aix.dfw.ibm.com spsn1
These steps assume that the host names (the output of the hostname command) on the nodes and control workstation were previously short and will remain that way after the conversion to DNS. There will be no host name changes. To get the short host names to use as you apply the following steps to your system, execute the command splstdata -n.

  1. Implement DNS on the nodes and control workstation. Then execute the host command to ensure that the name resolution is correct for the IP address of the adapters in the SP nodes and control workstation. The output should contain the fully qualified host name before any short aliases. Also make any necessary changes to /etc/hosts.

    The following is an example of the input and output for checking name resolution:

                   host spsn1
                   spsn1.aix.dfw.ibm.com is 9.19.174.1,  Aliases:   spsn1
                   host 9.19.174.1                                    |
                   spsn1.aix.dfw.ibm.com is 9.19.174.1,  Aliases:   spsn1
    
    NOTE: The lines following the host command should be identical.

  2. The reliable_hostname object of the Node class in the SDR must contain the fully qualified domain name (long name) for each node. To ensure that it does contain the domain names, use smitty sp_eth_dialog and enter the necessary information. You may also use the spethernt command. For example, for a five-node system whose first node's en0 host name is spsn1 with a subnet mask of 255.255.255.0 and a default route of 9.19.174.50, run the following command:
                   /usr/lpp/ssp/bin/spethernt 1 1 5 spsn1 255.255.255.0 9.19.174.50
    

  3. To verify that the initial host name has been changed to the long form of the reliable host name, execute splstdata -n. As noted previously, before this host name change, your system had short names as the initial host names (regardless of whether or not the host name corresponded to the en0 adapter). To change the host names back to short names, use smitty hostname_dialog and enter the correct information, specifically toggling Use Short or Long Hostnames to short. You can also make this change with the sphostnam command. On the same five-node system used as an example in step 2, to make the initial host name the short version of the en0 (reliable) network, execute the following command:
                   /usr/lpp/ssp/bin/sphostnam -a 'en0' -f 'short' 1 1 5
    

  4. Now the Switch_partition class needs to be changed to reflect the new long names. This is where Estart and Eprimary get their information about which node is primary, backup, and so on. The class contains node names which are the reliable host names of the nodes. Having completed steps 2 and 3, you have long names as reliable host names, but short names in the Switch_partition class. To change the names in the Switch_partition class, execute the Eprimary command, specifying which node to be the oncoming primary and oncoming primary backup. Then execute Estart. Here is an example of using both commands:

       Eprimary 1 -backup 5 (specify -backup for the SP Switch)
       Estart

    Estart will complete the cycle and copy the necessary information into the Switch_partition class.



[ Doc Ref: 90605200514618     Publish Date: Oct. 26, 2000     4FAX Ref: 7459 ]