akka

usage: akka <subcommand> <arguments>

This command allows you to manage Akka clusters. For further information on Akka clusters, see /wiki/spaces/MD82/pages/3778595 in the System Administration guide.

The akka command has eight subcommands: cluster-status, down, is-available, is-singleton, leaders, members, member-status and unreachable. You must provide the name of the cluster and an SC in regex for all of the subcommands.

Hint!

You can enter a specific SC, or you can use ".*" to run the command for all of the SCs in a cluster.

You can use the following subcommands with the akka command:

  • cluster-status
  • down
  • is-available
  • is-singleton
  • leader
  • members
  • member-status
  • unreachable

Arguments

ArgumentDescription
<cluster-name>The name of the akka cluster
<sc in regex>The SC that the akka cluster is on in regex
<cluster node address>The address of the cluster node

cluster-status

usage: akka cluster-status <cluster name> <sc in regex>

Use akka cluster-status to get the current status for a specific akka cluster, e g information is provided on the member ring, available nodes, meta data etc. 

Example - Using the command mzsh akka cluster-status

If you require information on the status of the cluster for your System Insight Akka cluster on one of the SCs:

$ mzsh akka cluster-status si sc5

The output returned is:

{
  "sc5": {
    "leader": "akka.tcp://si@172.27.239.120:6101",
    "members": [{
      "address": "akka.tcp://si@172.27.239.120:6101",
      "roles": ["si"]
    }],
    "unreachable": [],
    "roles": [{
      "name": "si",
      "leader": "akka.tcp://si@172.27.239.120:6101"
    }]
  }
}

down

usage: akka down <cluster name> <sc in regex> <cluster node address>

Use akka down to send a request to mark the node with the address that you provide as DOWN. For example, if one node in a cluster fails in a cluster of several nodes, you can tell the reachable nodes to remove the unreachable node using this command. For an example scenario, see /wiki/spaces/MD82/pages/3778761.

Example - Using the command mzsh akka down

If you want to mark a cluster address for your System Insight as down:

$ mzsh akka down si sc5 akka.tcp://si@172.17.0.1:6151

is-available

usage: akka is-available <cluster name> <sc in regex>

Use akka is-available to find out if the availability of a node or nodes on a specific cluster. The output that you receive is true or false.

is-singleton

usage: akka is-singleton <cluster name> <sc in regex>

Use akka is-singleton to find out if a specific cluster has a single node or not. The output that you receive is true or false.

leader

usage: akka leader <cluster name> <sc in regex>

Use akka leader to find out who the current leader is for a cluster. The cluster address of the leader is returned.

Example - Using the command mzsh akka leader

If you want to know which is the current leader for your Conditional Trace Akka cluster:

$ mzsh akka leader akka-trace-cluster ".*"

The cluster address of the leader is provided for each node:

"sc1": "akka.tcp://akka-trace-cluster@172.27.239.120:5501"
"sc2": "akka.tcp://akka-trace-cluster@172.27.239.120:5501"
"sc3": "akka.tcp://akka-trace-cluster@172.27.239.120:5501"

members

usage: akka members <cluster name> <sc in regex>

Use akka members to list the addresses of the members for a specific cluster.

Example - Using the command mzsh akka members

If you require to know which members there are for your Conditional Trace Akka cluster:

$ mzsh akka members akka-trace-cluster sc1

The members are provided:

{
  "sc1": [{
    "address": "akka.tcp://akka-trace-cluster@172.27.239.120:5501",
    "roles": ["default"]
  }, {
    "address": "akka.tcp://akka-trace-cluster@172.27.239.120:5551",
    "roles": ["default"]
  }, {
    "address": "akka.tcp://akka-trace-cluster@172.27.239.120:5601",
    "roles": ["default"]
  }, {
    "address": "akka.tcp://akka-trace-cluster@172.27.239.120:6051",
    "roles": ["default"]
  }]
}

member-status

usage: akka member-status <cluster name> <sc in regex>

Use akka member-status to request the current status of a member node or member nodes. The output that you receive is Up or Down.

unreachable

usage: akka unreachable <cluster name> <sc in regex>

Use akka unreachable to find out which members of a specific cluster are unreachable. 

Return Codes

Listed below are the different return codes for the akka command:

CodeDescription
0Will be returned if the command is successful.
1Will be returned if the argument is invalid.