One of the things that the IBM Bluemix Platform (based on Cloud Foundry) supports is logging to external logging providers. I was recently reading Takehiko Amano’s excellent article on Splunk integration with IBM Bluemix. Splunk is becoming very popular in the industry generally for log aggregation, indexing, and searching.
Takehiko’s solution is excellent, but still requires somewhere to deploy Splunk. However, Bluemix itself provides the IBM Containers offerings (based on Docker technology) where Splunk can be run. This probably isn’t suitable for robust production environments, but for quick ‘n’ dirty testing, it’s really useful. I’ve documented below some steps that you need to get this up and running with Splunk Light, which is the simpler, lighterweight edition of Splunk.
You have a git client installed locally.
You have signed up for IBM Bluemix (Public) and have an ID to log in with.
Install Docker locally on your machine. This will give you access to the Docker command-line tools.
Instructions for this tutorial are written assuming you are using OS X, although they can probably be adapted to other platforms fairly easily.
Build the Splunk Container
You need to build the Docker container for Splunk locally before pushing it up to the Bluemix containers repository. There’s already a well-established GitHub project for a Splunk Docker container, but we need to add the RFC5424 add-on as per Takehiko’s article to get Splunk to recognize the logging format.
I’ve already forked the GitHub repository and added most of the changes required to do that, but you will need to download the add-on itself first.
Open a terminal and clone my repository, checking out the
git clone -b bluemix https://github.com/andrewferrier/docker-splunk/
Download the RFC 5424 add-on. You will need to sign up for a free splunk.com ID if you don’t already have one. Put the
.tgzfile in the
splunklightdirectory inside your checked-out git repository.
Now build the Docker image (which may take a little while):
cd <your_checkout_directory>/splunklight docker build -t andrewferrier/splunk:latest-light .
(If you wish, you can substitute your own namespace prefix in place of
andrewferrier - as long as you use it consistently below).
Push the Splunk Container up to Bluemix and start it running
Firstly, log into Bluemix and initialize the container runtime:
bx login bx ic init
You will need to specify an organisation and space within which to work on Bluemix.
Next, double-check what your IBM Containers “namespace” is. If you’ve worked
with Containers before, you’ve probably already got one specified. You can
check it with
bx ic namespace-get. If you haven’t, you’ll need to set
bx ic namespace-set (I use
andrewferrier, for example - but
you can set it as anything that’s meaningful to you - it will have to be
unique across all users using shared Bluemix).
Now, tag your built image to prepare it for upload to the remote registry:
docker tag andrewferrier/splunk:latest-light registry.ng.bluemix.net/andrewferrier/splunk:latest-light
(Note that the first
andrewferrier above is the prefix we specified
previously when we build the image. The second is the namespace on Bluemix
itself as just discussed. If you want to work with the UK instance of Bluemix,
rather than the US one, change all references to
Now actually push the image to the remote registry (this may take a little while):
docker push registry.ng.bluemix.net/andrewferrier/splunk:latest-light
Now, we need to create some persistent volumes for both the
/opt/splunk/var filesystems within the container:
bx ic volume create splunk-etc bx ic volume create splunk-var
Start the container running. Notice that we are exposing two TCP ports,
8000 (which will be used over HTTP to access the Splunk console), and
(which will be used to push syslog messages from Bluemix to Splunk).
bx ic create -m 1024 -p 8000 -p 5140 --env SPLUNK_START_ARGS="--accept-license" --volume splunk-etc:/opt/splunk/etc --volume splunk-var:/opt/splunk/var registry.ng.bluemix.net/andrewferrier/splunk:latest-light
Once the container has started running, the Bluemix CLI will print out the
container ID. You typically only need the first few characters - enough to
uniquely identify it (e.g.
Now check which public IP addresses you have free to assign to the container:
bx ic ips
This should print a list of IPs (probably two if you are working with a trial Bluemix account) - pick any IP which is not assigned to a container (if you have no unassigned addresses, you’ll either need to pay for more or unbind one from an existing container first). Now bind that IP address to your newly-created container:
bx ic ip-bind 188.8.131.52 abc1234
Now you’ll need to create a user-provided service to stream the logs from your application(s) to Splunk:
bx cf cups splunk -l syslog://184.108.40.206:5140
Setting up a TCP listener within Splunk
Now we need to set up a data listener within Splunk to listen for data on TCP port 5140 (essentially, this is the same procedure as Takehiko’s original article).
Open the Splunk console in a browser using the URL
(obviously, change the IP address for the one you picked above). Log in using
the default username/password pair
admin/changeme (Splunk will then
encourage you to immediately change the password, which you should).
On the home screen, click “Add Data” to add a data source:
Select “TCP/UDP” to add a TCP-based data listener:
Enter Port 5140 (the same port we exposed from the Splunk Docker container above):
rfc5424_syslog as the source type (which corresponds to the Splunk
add-on we installed previously). You may find it easiest to type
the dropdown box to select this. Also, you may want to create a new index to
index data from Bluemix. In this case, I’ve created one called
Review the settings you’ve entered and add the data listener.
Clone and push a demo application
In this article, we’ll clone a sample Node.JS application locally and then push it to Bluemix, so we can bind it to the user-provided service we just defined to use it to test the Splunk integration.
cd <some_temporary_directory> git clone https://github.com/IBM-Bluemix/get-started-node cd get-started-node curl https://new-console.ng.bluemix.net/get-started/docs/manifest.yml > manifest.yml
Now edit manifest.yml to change
host to a unique name (e.g.
TestAppForSplunkAF (note that this name must be unique within the whole of
Bluemix, which is why I use my initials to make this unique).
You also need to modify lines of the
server.js file to look like this:
var port = process.env.VCAP_APP_PORT || 8080;
(This ensures that the application will pick up the correct port number from the Bluemix deployed environment).
Now push the application up to Bluemix:
bx cf push
Bind that service to any application you wish:
bx cf bind-service TestAppForSplunkAF splunk
And restage each application:
bx cf restage TestApp
Testing the logging mechanism
Probably, just in the act of restaging your application, you’ll already have
generated some logs. However, to make things a bit more interesting, open the
endpoint for your application (e.g.
or similar, modify for the name of your application!) in a browser, and
refresh it a few times.
Now, you should start to see your logging information appearing through
Splunk. Assuming you set Splunk up as shown above, and created a new
non-default index called
bluemix, you should simply be able to search for
everything in the
You should see some search results appear like this:
The world is now your Oyster! You can use any standard Splunk searching mechanism to find logs.
Any questions or comments, contact me at andrew DOT ferrier AT uk DOT ibm DOT com.