Home
Administering
In addition to administering the database server, you can tune performance, replicate data, and archive data.
System administration
These topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL Informix® database servers.
Administrator's Guide
The Informix® Administrator's Guide provides the information required to administer HCL Informix.
Logging and log administration
Manage logical-log files
Free a logical-log file
Free a log file with status U

Administering
In addition to administering the database server, you can tune performance, replicate data, and archive data.
- System administration
  These topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL Informix® database servers.
  - List of utilities
    HCL Informix® includes utilities and applications that you can use to perform administrative tasks and capture information about configuration and performance.
  - Administrator's Guide
    The Informix® Administrator's Guide provides the information required to administer HCL Informix.
    - The database server
    - Disk, memory, and process management
    - Logging and log administration
      - Logging
      - Manage the database-logging mode
        You can monitor and modify the database-logging mode.
      - Logical log
      - Manage logical-log files
        Estimate the size and number of log files
        Back up logical-log files
        Switch to the next logical-log file
        Free a logical-log file
        Delete a log file with status D
        Free a log file with status U
        Freeing a log file with status U-B or F
        If a log file is backed up but still in use (status U-B), some transactions in the log file are still under way, or the log file contains the oldest update that is required for fast recovery. Because a log file with status F has been used in the past, it follows the same rules as for status U-B.
        Freeing a log file with status U-C or U-C-L
        Free a log file with status U-B-L
        If a log file is backed up and all transactions within it are closed but the file is not free (status U-B-L), this logical-log file contains the most-recent checkpoint record. You can free log files with a status U-B-L.
        Monitor logging activity
        Allocate logical log files
        When you initialize or restart the database server, it creates the number of logical-log files that are specified by the LOGFILES configuration parameter. The size of the logical log files is specified by the LOGSIZE configuration parameter.
        Dropping logical-log files
        You can use an onparams command to drop logical-log files.
        Change the size of logical-log files
        Move logical-log files
        You might want to move logical-log files for performance reasons or to make more space in the dbspace.
        Display logical-log records
        Controlling long transactions
      - Physical logging, checkpoints, and fast recovery
      - Manage the physical log
    - Fault tolerance
    - High availability and scalability
      A successful production environment requires database systems that are always available, with minimal if any planned outages, and that can be scaled quickly and easily as business requirements change.
    - Distributed data
    - Overview of automatic monitoring and corrective actions
      You can use the SQL administration API, the Scheduler, and drill-down queries to manage automatic maintenance, monitoring, and administrative tasks.
  - Administrator's Reference
    The Informix® Administrator's Reference includes comprehensive descriptions of HCL Informix configuration parameters, the system-monitoring interface (SMI) tables in the sysmaster database, the syntax of database server utilities such as onmode and onstat, logical-log records, disk structures, event alarms, and unnumbered error messages.
  - DB-Access User's Guide
    The Informix® DB-Access User's Guide describes how to use the DB-Access utility to access, modify, and retrieve information from Informix database servers.
  - High-Performance Loader User's Guide
    The describes how to use the HCL Informix® to load and unload large quantities of data efficiently to or from Informix databases.
  - Performance Guide
    The Informix® Performance Guide describes how to configure and operate your HCL Informix database server to improve overall system throughput and to improve the performance of SQL queries.
  - SNMP Subagent Guide
    The describes the Simple Network Management Protocol (SNMP) and the software that you need to use SNMP to monitor and manage HCL Informix® database servers and databases.
  - InformixHQ Guide
    InformixHQ is a modern web console for visualizing, monitoring, and managing your Informix server instances. It is purpose built for ease-of-use, scaling out, and optimizing DevOps needs. It provides critical performance management capabilities, monitoring how key performance metrics are changing over time and tracking how efficiently Informix is running your workload even when you’ve stepped away from your screen. Its monitoring system feeds directly into a customizable alerting system so you can be immediately alerted via email, Twilio, or PagerDuty whenever an issue occurs on one of your Informix database server instances. InformixHQ is designed to be scalable to efficiently manage and monitor as many Informix database server instances as you need. Moreover, it's a tool that can be shared by the DBAs, the app developers, the ops engineers, and management and accessed from any desktop, laptop, or mobile device. InformixHQ is the centralized hub for graphical monitoring, alerting, and administration of your Informix database servers.
- Backup and Restore Guide
  The Informix® Backup and Restore Guide describes how to use the Informix ON-Bar and ontape utilities to back up and restore database server data. These utilities enable you to recover your databases after data is lost or becomes corrupted due to hardware or software failure or accident.
- Enterprise Replication
  The HCL® Informix® Enterprise Replication Guide describes the concepts of data replication using Informix Enterprise Replication, including how to design your replication system, as well as administer and manage data replication throughout your enterprise.

Free a log file with status U

If a log file contains records, but is not yet backed up (status U), back up the file using the backup tool that you usually use.

If backing up the log file does not change the status to free (F), its status changes to either U-B or U-B-L. See Freeing a log file with status U-B or F or Free a log file with status U-B-L.