Chapter 7 HPSS User Interface ConfigurationHPSS Installation Guide September 2002 449Release 4.5, Revision 2The fifth file (filesys.dat) is automatically updated by HDM as new aggregates and filesets arecreated. Therefore, this file should not ordinary be edited by the administrator. HDM cannot bestarted if this file is missing or does not contain correct information. Before starting HDM for thefirst time, a special version of filesys.dat must be created so that HDM will recognize that the file iscorrect.It is possible to run multiple instances of HDM on one machine. For example, one HDM might beused to handle mirrored aggregates, while another might be used to handle archived aggregates.To set up a system in this manner, be sure to keep the associated configuration and log files inseparate directories. For example, /var/hpss/hdm/hdm1 and /var/hpss/hdm/hdm2.Since logs necessary for HDM are heavily used and vital, it is recommended that configurationdirectories and the directories where the logs are stored be placed on file systems that are mirroredand have low latencies. Also, the log files defined in the config.dat must exist before the HDM isrun. Simply use the touch command to create these files if they do not exist already. For XFS, anadditional file, nshandle.dat, must also exist before the HDM is run. Create it using the touchcommand.7.6.3.3.1 config.dat FileThe basic configuration file, config.dat, is a text file that defines the configuration of an HDM server.It is recommended that the file be kept in the directory /var/hpss/hdm/hdm.The file consists of a series of lines, where each line defines one parameter. The first field on the linespecifies the name of the parameter and the second field is the value for that parameter. The firstline in the file must define ServerID. The following lines define the rest of the parameters. ServerIDmust begin in column one, while the other parameters must be indented by at least one tabcharacter. The file may contain comments that start with a ‘#’ character and continue until the endof the line.ServerID is an arbitrary number used to distinguish different HDM servers defined in theconfiguration file. Once ServerID has been established, it should not be changed because it is usedduring event recovery whenever HDM is restarted. A good choice for ServerID is 1, since this isthe default used by hdm_admin. HDM can be started with the command:hdm_admin start /var/hpss/hdm/hdm/config.dat where ServerID is a number identifying which part of the configuration file HDM should read.Following is an extract from a typical configuration file:# An example HDM configuration fileServerID 1DescName Production configurationRegisterBitMap 0.0 #A comment[...]Refer to the template file, /opt/hpss/config/templates/hdm_config.dat.template when constructinga config.dat file.
