Getting cluster information from ZooKeeper

3 minute read

Use ClusterInfoTool to get information on the running CloudBees Flow server cluster from ZooKeeper.

Prerequisites

  • The CloudBees Flow server cluster must be installed and running on the network.

  • Configuration files that all CloudBees Flow server nodes will use in a clustered configuration must be uploaded to the Apache ZooKeeper server using the ZKConfigTool.

  • The ZooKeeper cluster must be running an odd number of Zookeeper nodes, and there must be a leader node.

  • The system must be running a version of Java supported by CloudBees Flow.

    For the correct version requirement, see Java Requirements . Java is automatically installed with the CloudBees Flow software as part of the Tools installation.

Locations

The CloudBees Flow installer adds the ClusterInfoTool to the following default locations:

  • Windows: C:\Program Files\Electric Cloud\ElectricCommander\server\bin\cluster-info-tool-jar-with-dependencies.jar

  • Linux: /opt/electriccloud/electriccommander/server/bin/cluster-info-tool-jar-with-dependencies.jar

ClusterInfoTool Command Syntax

ClusterInfoTool requires that the DCOMMANDER_ZK_CONNECTION environment variable is set so that it can locate your ZooKeeper nodes. You can set the variable by using the Linux export command beforehand or inline as part of the command for the ClusterInfoTool command itself:

$ export COMMANDER_ZK_CONNECTION=<ZooKeeper_Server1_IP>:2181,<ZooKeeper_Server2_IP>:2181,<ZooKeeper_Server3_IP>:2181
$ java -jar cluster-info-tool-jar-with-dependencies.jar [<arguments>]

or

$ java -DCOMMANDER_ZK_CONNECTION=<ZooKeeper_Server1_IP>:2181,<ZooKeeper_Server2_IP>:2181,<ZooKeeper_Server3_IP>:2181 -jar cluster-info-tool-jar-with-dependencies.jar [<arguments>]
ArgumentDescription

--user < flow_username >

(Optional) Specifies the CloudBees Flow server username to connect. You are prompted for a username if you do not specify this argument.

--password < flow_password >

(Optional) Specifies the CloudBees Flow server user password to connect. You are prompted for a password if you do not specify this argument.

--serverUrl < flow_server_url >

(Optional) Specifies the CloudBees Flow server URL to connect. You are prompted for the URL if you do not specify this argument.

--ignoreCerts

(Optional) Ignores non-trusted self-signed certificates

--cleanJGroupsData

(Optional) Clears out JGroups cluster data

--help

(Optional) Shows usage information

Sample Command Usage and Output

This is sample output generated by ClusterInfoTool :

$ cd /opt/electriccloud/electriccommander/server/bin
$ export COMMANDER_ZK_CONNECTION=chronic3-zk1:2181,chronic3-zk2:2181,chronic3-zk3:2181
$ java -jar cluster-info-tool-jar-with-dependencies.jar --user charvey --ignoreCerts --serverUrl \https://chronic3java
Using ZooKeeper connection string: chronic3-zk1:2181,chronic3-zk2:2181,chronic3-zk3:2181
Please enter the CloudBees Flow User Password: myPassword1
There are 3 ZooKeeper nodes in the ensemble: chronic3-zk1:2181, chronic3-zk2:2181, chronic3-zk3:2181
Connecting to ZooKeeper node chronic3-zk1:2181
Connected to chronic3-zk1:2181, attempting to get status
chronic3-zk1:2181 is a follower
Connecting to ZooKeeper node chronic3-zk2:2181
Connected to chronic3-zk2:2181, attempting to get status
chronic3-zk2:2181 is a follower
Connecting to ZooKeeper node chronic3-zk3:2181
Connected to chronic3-zk3:2181, attempting to get status
chronic3-zk3:2181 is a leader
ZooKeeper ensemble looks healthy, chronic3-zk3:2181 is the leader
Connecting to ZooKeeper ensemble at chronic3-zk1:2181,chronic3-zk2:2181,chronic3-zk3:2181
Connected to ZooKeeper ensemble
Reading data at /commander/conf/commander.properties
Loaded data at /commander/conf/commander.properties
Parsed data at /commander/conf/commander.properties
COMMANDER_SERVER_NAME property value: chronic3.electric-cloud.com
Reading data at /commander/conf/database.properties
Loaded data at /commander/conf/database.properties
Parsed data at /commander/conf/database.properties
Reading data at /commander/conf/passkey
Loaded data at /commander/conf/passkey
Parsed passkey at /commander/conf/passkey
Reading data at /commander/conf/keystore
Loaded data at /commander/conf/keystore
Parsed keystore at /commander/conf/keystore
Checking JGroups data in ZooKeepr
Checking /commander/jgroups/activeMQ:
    e3f11bbd-5773-34b5-cb23-328fb873e266 ->
        chronic3e-34229     e4a26872-9a45-8110-de5d-cc6786ffae92     192.168.2.212:5446     F
        chronic3d-47613     e3f11bbd-5773-34b5-cb23-328fb873e266     192.168.2.211:5446     T
        chronic3c-52982     31a5e860-f30f-6e27-ff7c-de746332f742     192.168.2.210:5446     F
        chronic3a-10319     7e0ecd44-02f7-8441-4fcc-134a192784c8     192.168.2.208:5446     F
Checking /commander/jgroups/commander:
    9678311d-68ed-eaf5-e887-c3c3e4f0c645 ->
        chronic3a-35854     3c114e9a-4fb4-cdb0-9542-3f03611cb9d0     192.168.2.208:5447     F
        chronic3c-29085     4978a555-9278-e0af-0f70-73af1eadc7c0     192.168.2.210:5447     F
        chronic3e-12173     30269f49-0bbe-bc9b-86c9-09c525d7cffb     192.168.2.212:5447     F
        chronic3d-25124     9678311d-68ed-eaf5-e887-c3c3e4f0c645     192.168.2.211:5447     T
Server IP address (This server property should be set with a value that points to the CloudBees Flow Server Load Balancer FQDN): chronic3.electric-cloud.com
Stomp Client URI: stomp+ssl://chronic3.electric-cloud.com:61613
Use SSL for Stomp: false

Interpreting ClusterInfoTool Command Output

How to interpret ClusterInfoTool output:

  • The nodes /commander/jgroups/activeMQ and /commander/jgroups/commander contain information on these JGroups clusters:

    • commander for the CloudBees Flow server cluster

    • activeMQ for the activeMQ cluster

  • The child nodes under each JGroups node represent the participating CloudBees Flow servers in the cluster. Each child node entry is in this form:

    <Logical_Name>   <UUID>   <IP_address>:<port>   T|F
  • The number of entries in both JGroups nodes should be the same, with matching IP addresses but with different port numbers and distinct logical names and UUIDs. The coordinator node in each JGroups cluster is identified with a ‘ T ’ against its entry.