Remote Execution in Clusters#
When commands are run on a cluster, a number of options are available to specify the nodes on which the commands can be run.
There is a <where> clause: cluster run <where>.
The clause can take:
role - the role of the node:
application
,database
,webproxy
all
- all the roles, in other words, the entire clusternotme
- all nodes except the one the command is run on<data center name>
- all nodes in the data center<nodename|IP>
- the hostname or IP address of the node.
For example:
cluster run database app start mongodb will restart the mongodb service on all database nodes.
cluster run all app status will display the app status of all nodes on the cluster.
cluster run notme system shutdown would issue the command to shut down all nodes except the one the command is run on.
Important
In a cluster, reboot and shutdown of the entire cluster should be done on each node and not with the cluster run all command.
Sometimes there are long-running processes running on a server. To display such jobs, use the cluster job list command.
Note
The cluster job list command is not available on a web proxy node.
It is also possible to re-attach to those jobs to see the output, using cluster job reconnect <pid>.