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Altair FlowTracer Administrator Guide
This manual is aimed at the person who will be the administrator for FlowTracer. This person will be responsible for configuring the network resources, setting up the licensing, and establishing security and access rules for the system.
Manage the Server for a Project
Time Tolerance

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Altair FlowTracer User Guide
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Altair FlowTracer Administrator Guide
This manual is aimed at the person who will be the administrator for FlowTracer. This person will be responsible for configuring the network resources, setting up the licensing, and establishing security and access rules for the system.
- FlowTracer Roles
  When using FlowTracer in large deployments, three main roles emerge: Administrator, Developer and User. In smaller organizations, a given person may have multiple roles, but the duties of each role still exist.
- Enable CLI Access on UNIX
  This section explains how to set up a UNIX user's shell environment to have a proper context for the user to run installed Altair Accelerator programs from the command line. The programs that are run from the command line are called the CLI commands.
- Enable CLI Access on Windows
  This section explains how to set up a Window user's command prompt environment to have the proper context for the user to run installed Altair Accelerator programs from the command line. The programs that are run from the command line are called the CLI commands.
- User Interfaces
- Use FlowTracer Help
  FlowTracer documentation is available in HTML and PDF format.
- Projects
- Server Working Directory
  When a project is created, a server working directory (.swd directory) is created to hold configuration and state information about the project.
- Alerts
  VOV issues an "alert" when an event requires attention. An alert can range from information that does not require action to an urgent fault that requires immediate action.
- Manage the Server for a Project
  - Port Number
    The project name is normally used to compute the number of the TCP port on which the vovserver listens for connections. This is done by hashing the project name into the port range 6200-6455, using the function vtk_port_number.
  - Advanced Control of the Product Ports
  - Server Configuration
    vovserver configuration parameter values may be changed in a running vovserver using the CLI, or prior to the starting the server via the policy.tcl file. An administator can configure the parameters in the running vovserver using the vovservermgr command or the vtk_server_config procedure.
  - Web Server Configuration
  - VOV Protocol Summary
  - Time Tolerance
  - Client Limitation and Tuning
    The maximum number of clients - the combination of vovtaskers, user interfaces and proxies, that can be concurrently connected to a vovserver is limited by the number of file descriptors available.
  - Safe Server Threads
    As the server farm becomes larger and larger, it becomes useful to allow the vovserver to use multiple threads to handle the costly read-only services, such as listing sets of jobs or retrieving the complete list of taskers.
  - Set the Range for VovId
    A VovId is a nine-digit string assigned by VOV to each object in the trace.
  - Server Configuration Parameters
  - Troubleshooting the Server
  - Change the Project Name, Server Host, or User
  - Log Files
  - Autostart Directory
    With the command vovautostart, on vovserver startup, scripts can be specified to execute automatically.
  - Autostop Directory
    With the command vovautostop, on vovserver shutdown, scripts can be specified to execute automatically.
  - Run Periodic Tasks
  - Job Status Triggers
    The daemon vovtriggerd taps the event stream and executes commands that are based on selected events.
- Security
  The VOV security model consists of assigning a Security Code to each client or client group (VovUser Group) and granting the permission to execute critical tasks only to clients with the appropriate security level.
- Taskers
  A tasker is a VOV client that provides computing resources, specifically CPU cycles, to the vovserver.
- Interfaces to Accelerator, SGE, LSF, and Others
  FlowTracer can be used also as a front end to an existing batch processing system (BPS), for example, Accelerator, LSF, SGE, SGEEE, etc.
- Configuration for Elastic Computing
- Configuration for Altair Accelerator
- Configure a Failover Server Replacement
  If a server crashes suddenly, VOV has the capability to start a replacement server on a pre-selected host. This capability requires that the pre-selected host is configured as a failover server.
- Advanced Information
- Multi-User Altair FlowTracer
  FlowTracer now supports a "multi-user" mode of operation, as a Beta feature. In the multi-user mode, many different users can share the same project, in terms of modifying a flow as well as running different compoments of the flow.
- IT Administrator Topics
- Special Issues
- Miscellaneous
Altair FlowTracer Developer Guide

Time Tolerance

The file server (or servers) and the vovserver may be unsynchronized. If that occurs, comparing the timestamp of a file with the start time of a job, may produce an incorrect result due to the clock offset.

While it is easy to synchronize the clocks, it may be occasionally necessary to run VOV on a network that is slightly offset.

Tolerance can be set to accept timestamp comparisons with a tolerance of a few seconds. A typical value for the tolerance is less than 10 seconds. By default, no tolerance is allowed; it is assumed that the network is synchronized.

Setting the Tolerance

Time tolerance is set by adding a line in the policy.tcl file. Example:

set config(timeTolerance) 2

The tolerance can also be set via the browser interface. To do so, log in as ADMIN and visit the Admin page.