Customizing PubSub+ Cache Configuration Files

Each installed PubSub+ Cache Instance process receives its configuration parameters through two sources:

  • a configuration file for the instance, specified at invocation (used to connect to the event broker)
  • the Designated Router—the PubSub+ Cache Instance learns additional configuration information from the Designated Router through the event broker message bus

Each PubSub+ Cache Instance requires its own configuration file, which must be filled out with specifics for your configuration. The sampleConfig.txt file (included with the PubSub+ Cache installation package) is provided as a template.

The parameters that are passed to an installed PubSub+ Cache Instance through the PubSub+ Cache Instance configuration file includes:

  • the client username and password to use when connecting to the event broker
  • the DNS name or IP address of the event broker to connect to and, optionally, the DNS name or IP address of a backup event broker to connect to if the preferred event broker is unreachable
  • the Message VPN to join
  • a unique name that is used to identify the PubSub+ Cache Instance in Solace CLI, and on the event broker message bus
  • the local priority and network priority of the PubSub+ Cache Instance (optional parameters).
  • the Processor Mask (an optional parameter used to specify which computer processors the PubSub+ Cache Instance can run on)
  • the name of the file to use when backing up the PubSub+ Cache Instance’s cached messages (see Performing PubSub+ Cache Administrative Tasks)

To customize the PubSub+ Cache Instance configuration file, perform these steps:

  1. Following the instructions provided within the sampleConfig.txt file, edit a copy of the file with the specifics for your PubSub+ Cache Instance configuration.

    Ensure that the CACHE_INSTANCE_NAME is the same PubSub+ Cache Instance name that was used for the matching PubSub+ Cache Instance object configured through the Solace CLI (see Configuring PubSub+ Cache Instances).

  2. Save the modified configuration file with a unique identifying file name to one of the following locations:
  • If the PubSub+ Cache Instance is to run on a Linux computer, save the file on that Linux computer.
  • If the PubSub+ Cache Instance is to run on an event broker, save the file to
    /usr/sw/solcache/config on that event broker.

Changing PubSub+ Cache Configuration Files While in Use

If you modify the configuration parameters for a PubSub+ Cache Instance process, you can apply the changes using either of the following methods:

  • Stop and restart the PubSub+ Cache Instance process. When the PubSub+ Cache Instance restarts, it uses the updated configuration parameters provided in the file.
  • Use the PubSub+ Cache service script's “service solcache reload” command to reload the PubSub+ Cache Instance configuration parameters without stopping the PubSub+ Cache Instance process. When you run this command, the script sends a SIGUSR1 signal to the PubSub+ Cache Instance. Upon receiving the signal, the PubSub+ Cache Instance re‑reads its configuration file and changes any properties that can be reloaded. See the sampleConfig.txt configuration file (included with the PubSub+ Cache Instance installation package) for information about which parameters are reloadable.