HPSS Installation Guide September 2002 413Release 4.5, Revision 2Chapter 7 HPSS User InterfaceConfiguration7.1 Client API ConfigurationThe following environment variables can be used to define the Client API configuration:The HPSS_LS_NAME defines the CDS name of the Location Server RPC Group entry for the HPSSsystem that the Client API will attempt to contact. The default is /.:/hpss/ls/group.The HPSS_MAX_CONN defines the number of connections that are supported by the Client APIwithin a single client process. If HPSS_MAX_CONN is set to zero, the number of connections isequal to the default supported by the HPSS connection management software - currently 150. IfHPSS_MAX_CONN is nonzero, it is the number of connections to be used.The HPSS_KTAB_PATH defines the name of the file containing the DCE security keys necessaryfor successfully initializing the Client API. The default is /krb5/hpssclient.keytab.The HPSS_HOSTNAME environment variable is used to specify the hostname to be used forTCP/IP listen ports created by the Client API. The default value is the default hostname of themachine on which the Client API is running. This value can have a significant impact on datatransfer performance for data transfers that are handled by the Client API (i.e., those that use thehpss_Read and hpss_Write interfaces).The HPSS_TCP_WRITESIZE environment variable is used to specify the amount of data to bewritten with each individual request to write data to a network connection during a data transfer.For some networks, writing less than the entire size of the client buffer has resulted in improvedthroughput. This environment variable may not affect the actual value used, depending on theHPSS network options file - see Section 6.10.2 for further details.The HPSS_TRANSFER_TYPE environment variable is used to specify the data transportmechanism to be used for data transfers handled by the Client API. The only valid value is TCP forTCP/IP transfer. The default value is TCP.The HPSS_PRINCIPAL environment variable is used to specify the DCE principal to be used wheninitializing the HPSS security services. The default value is hpss_client_api. This variable isprimarily intended for use by HPSS servers that use the Client API.
