Installing WombatOAM for PCF

This topic describes how to install WombatOAM for PCF.

Install WombatOAM

  1. Download the product file from Pivotal Network.

  2. Navigate to the Ops Manager Installation Dashboard and click Import a Product to upload the product file.

  3. Click Add next to the uploaded WombatOAM tile in the Ops Manager Available Products view to add it to your staging area. WombatOAM for PCF tile added

  4. Click on the newly added WombatOAM tile and review each configuration pane. WombatOAM for PCF tile not yet configured

  5. Set network if necessary. If you make any changes to the configuration, click Save. WombatOAM for PCF AZ and Networks

  6. Import the stemcell if necessary. The appropriate stemcell can be downloaded from bosh.cloudfoundry.org. WombatOAM for PCF Stemcell configuration

  7. Return to the Ops Manager Installation Dashboard and click Apply Changes to install WombatOAM tile. WombatOAM for PCF tile install

Log in to the WombatOAM Dashboard

  1. From the Wombat OAM tile, select the Credentials tab and click on the Links to credentials link in the App Credentials row. WombatOAM Credentials link

  2. Copy the password and remove the characters that are neither letters nor digits. This is the WombatOAM admin password.

    Example: If the App Credentials row shows LuAVRWeZyNR-PM3BC7F2rz-bmfecYShw, your password is LuAVRWeZyNRPM3BC7F2rzbmfecYShw. WombatOAM Credentials

  3. Navigate to https://wombat.YOUR-SYSTEM-DOMAIN and log in with the user name admin and the password from the previous step. WombatOAM Web Dashboard Login

Set Up WombatOAM to Monitor Erlang Nodes

To connect Erlang nodes with WombatOAM, you create a topology in the WombatOAM dashboard as follows:

  • Collect information about your nodes
  • Add the WombatOAM server as a node, and
  • Add each node that you want to monitor.

Collect Node Information

  1. In Ops Manager, click the WombatOAM tile and select the Status tab. Record the IP address of the WombatOAM machine. WombatOAM for PCF Status tab

  2. Find the connection details of the RabbitMQ nodes by connecting to one of the machines hosting a RabbitMQ server (e.g. by using SSH) and collect the followings

    1. Erlang node name. This can be found in the /var/vcap/store/rabbitmq/etc/rabbitmq/rabbitmq-env.conf file. An example node name is rabbit@dddcb00baa7295e1b123f2e412b137e7.
    2. Erlang cookie. This is stored in /var/vcap/store/rabbitmq/.erlang.cookie. The cookie is the same across the whole RabbitMQ cluster. An example cookie is 5ec65769aa6defb72941a0b70080e63c.
    3. Erlang network rules. These are found in the /var/vcap/store/rabbitmq/erl_inetrc. The host entries are the relevant entries for us, e.g.:

      {host, {10,65,179,56}, ["dddcb00baa7295e1b123f2e412b137e7"]}.
      {host, {10,65,179,57}, ["8fc424a52a3e77c0f5be9e0fd4063a25"]}.
      

Add the WombatOAM Node

Add a node representing WombatOAM, and enable it to connect to your RabbitMQ nodes.

  1. From the WombatOAM web dashboard. Select Topology > Add Node. Adding a Node to WombatOAM

  2. Add the WombatOAM server by completing these fields:

    1. Node name: wombat@WOMBAT_MACHINE_IP_ADDRESS
    2. Cookie: wombat
    3. Discover connected nodes: Leave unselected.
  3. Click Add node.
    Result: The WombatOAM node appear on the left within seconds. Node Added to WombatOAM

  4. Select Services > Execute and open the WombatOAM node family in the left panel. Click the WombatOAM node name and select Evaluate Erlang expression. Adding an Inet Rule to WombatOAM

  5. For all of the network rules you collected from the RabbitMQ node, evaluate the expression wo_inet_rules:add_host({COMMA-DELIMITED-IP},["RULE-ID"] using the IP address and ID for the rule.

    Example:

    wo_inet_rules:add_host({10,65,179,56}, ["dddcb00baa7295e1b123f2e412b137e7"]).
    

    Purpose: These rules tell WombatOAM that when asked to connect to a node specified by host name, it should connect to the given IP address rather than try to resolve the host name. WombatOAM stores these rules in a persistent database. The Result of Adding an Inet Rule

  6. The inet rules can be viewed by evaluating the following Erlang expression: wo_inet_rules:get_rules(). Checking the Inet Rules Stored in WombatOAM

Add Erlang Nodes

For each node you want to monitor with WombatOAM, do the following:

  1. From the WombatOAM web dashboard. Select Topology > Add Node.

  2. Complete these fields:

    1. Node name: Specify the Erlang node name that you collected.
    2. Cookie: specify the Erlang cookie that you collected.
    3. Discover connected nodes: To add a whole cluster in one step, select this box. To add only one node, leave it unselected. Adding RabbitMQ nodes to WombatOAM
  3. Click Add node.
    Result: The managed node appears on the left within seconds. RabbitMQ nodes added to WombatOAM

Now WombatOAM collects metrics, notifications, and alarms from the Erlang nodes that you added. You can use the WombatOAM dashboard to inspect and perform operations on these nodes.

An example of the Metrics tab: WombatOAM Metrics

An example of the Alarms tab: WombatOAM Alarms

Note If a tile is redeployed, stopped or started, BOSH can decide to change its IP address. This is problematic if either the IP address of a managed node changes or if the IP address of WombatOAM itself changes. If the IP address of a node changes, you need to update the inet rule by calling wo_inet_rules:del_host(OldIP) and wo_inet_rules:add_host(NewIP, Host). If the IP address of the WombatOAM node changes, that is a bigger problem, because the data directory refers to the node name; so in that case, WombatOAM needs to be reinstalled.

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