Restrictions and limitations

  • FTP service uses the default port (21) for non-secure connection and explicit mode, and 990 port for implicit mode. Non-standard settings of FTP service are not supported.
  • The number of downloads that can be created depends on many factors, such as the number of running system processes or services. (On the average, the maximum number of downloads is about 40.) In order to be able to run more downloads, it is necessary to apply additional settings.

    The recommended way is to allow the Capture Server's Windows service to interact with desktop. To do this, go to Administrative Tools, click Services, point to the Server's service, select Properties from the context menu. In the Properties dialog box navigate to the "Log On" tab. In the "Log on as" group, select the "Local System account" radio button, check the "Allow service to interact with desktop" check box, and press OK. If the service is running you will need to restart it.

    The other way to allow more downloads requires editing the registry using the Registry Editor. WARNING: Using Registry Editor incorrectly can cause serious, system-wide problems that may require you to reinstall the system to correct them. When the "Allow service to interact with desktop" option is checked for the Server's service, it runs in the interactive window station. If this option is off, the service runs in the non-interactive window station. By default, the non-interactive window station has a desktop with 512 kilobytes heap, whereas the desktop of the interactive window station has 3 megabytes heap. The number of downloads is limited by the heap size. If you wish to run the service in the non-interactive window station (with "Allow service to interact with desktop" option switched off), you may increase the heap size of the non-interactive window station's desktop. Please read the Microsoft Knowledge Base for details, which you can find in the article INFO: COM Servers Activation and NT Windows Stations in the "Window Stations and Windows NT Resources" section.

  • The number of scheduled downloads that can run simultaneously depends on many factors, such as available physical memory, processor performance, the average time required for processing of one polled file, and the number of files coming from FTP sites. (Please note that this section is applicable to the scheduled downloads only.) For each download working in scheduled mode, the component collects messages that will be output to Status Monitor and to log files. These messages are output and deleted from the memory each time the server process runs (the frequency of running is set up in server process information dialog). The number of messages stored in memory can grow if there are too many files to download, and the server does not have enough time to process them. If this occurs, you need to adjust scheduling settings, and possibly the frequency of FTP Poll process as well. If you set up the server to make a smaller pause between sessions of the process, it will flush the status messages more often, and FTP Poll will consume less memory space. If you schedule FTP polling with a longer interval, or within a shorter period of time, the number of messages will decrease, which results in smaller memory space used as well. In order to determine, whether it is necessary to adjust your polling process, you can look at the log files created in the debug mode. There are a number of messages containing 'message generation' and 'message output to the server' times. If after a period of work, there are messages in the log file which were output long after their generation (the time difference is significantly more than the process frequency), this means that the process needs to be adjusted.
  • If the process contains two site configurations that are configured to download files from the same FTP site, use different Working directories for these configurations to avoid conflicts during downloading.