|Pivotal Cloud Foundry® (PCF)||1.6.x and later|
The purpose of this document is to help in calculating the total number of messages that the Loggregator produces over a given amount of time. This is useful when trying to scale your Loggregator environment to handle the number of messages you are producing.
- cf cli 
- Cloud Foundry Firehose plugin
Note: The following commands should be run from the Ops Manager VM.
How to install the Cloud Foundry Firehose plugin
Installing the plugin is really simple.
1. Log on to the CF CLI with your admin credentials:
cf api <your_cf_api_url>
2. Add the plugin repository:
cf add-plugin-repo CF-Community http://plugins.cloudfoundry.org/
3. Install the plugin:
cf install-plugin “Firehose Plugin” -r CF-Community
4. Install Pipe Viewer (PV):
apt-get install pv
Please run the following commands from the Ops Manager VM.
1. Connect via Single SHell (SSH) into the Ops Manager VM
2. Log on as admin into the cf cli
3. cf nozzle -n | pv -l -i10 -r >/dev/null
i.e. Loggregator is processing 460.4 messages a second. The output will refresh every 10 seconds.
Rule of thumb
The number of Dopplers should be approximately the total number of messages per second divided by 2000.
(Dopplers =1 per msgs/sec /2,000)
2. Traffic Controllers
You should have one Traffic Controller for every four Dopplers.
(Traffic Controllers = 1 for every 4 Dopplers)
For a Nozzle such as the firehose-to-syslog  Nozzle, you will require one instance per 10,000 msgs/sec.
(Nozzles = 1 for every 10,000 msgs/sec)
 Installing cf cli: https://docs.run.pivotal.io/cf-cli/install-go-cli.html.
 Scaling Loggregator: http://docs.pivotal.io/pivotalcf/1-7/opsguide/logging-config-opsman.html#scaling
 Firehose-to-syslog: https://github.com/cloudfoundry-community/firehose-to-syslog