Oracle Virtual Server (OVS): Command To Check All Servers Part of OVS Pool and Which Server is Master (How To Doc)

Below command can be used to check all Servers part of OVS pool and which Server is Master.

ovs-agent-db dump_db -c server_pool_servers

Below is example output of above command.

# ovs-agent-db dump_db -c server_pool_servers
{'ovm-server-01.test.com': {'node_number': 0,
                               'registered_ip': '10.10.10.1',
                               'roles': set(['master', 'utility', 'xen'])},
 'ovm-server-02.test.com': {'node_number': 1,
                               'registered_ip': '10.10.10.2',
                               'roles': set(['utility', 'xen'])},
 'ovm-server-03.test.com': {'node_number': 2,
                               'registered_ip': '10.10.10.3',
                               'roles': set(['utility', 'xen'])},
 'ovm-server-04.test.com': {'node_number': 3,
                               'registered_ip': '10.10.10.4',
                               'roles': set(['utility', 'xen'])}}

Products to which Article Applies

Oracle Virtual Server (OVS), Oracle VM Manager environments.

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LINUX: How to Enable Service On Linux Nodes Using Systemctl Command? (How To Doc)

On Linux 7 & above versions "chkconfig --list" command cannot be used for enabling the services.
We will have to use systemctl command to check and enable services on Linux 7 and above versions.

Follow below steps to enable the desired service on Linux OS using systemctl command.

1. Check the status of the service using below command.

systemctl list-unit-files | grep -i <service name>

Below is sample output which shows the status of docker as disabled.

# systemctl list-unit-files | grep -i docker

docker.service                                disabled

docker.socket                                 disabled

2. Enable the desired service using below command.

systemctl enable docker

Below is sample snippet of enabling the docker service using systemctl command.

# systemctl enable docker

Created symlink from /etc/systemd/system/multi-user.target.wants/docker.service to /usr/lib/systemd/system/docker.service.

3. Check the status of the service using below command.

systemctl list-unit-files | grep -i <service name>

You will see that the service is enabled. Below is the sample output which shows docker service as being enabled.

# systemctl list-unit-files | grep -i docker

docker.service                                enabled

docker.socket                                 disabled

Products to which Article Applies

All Host Operating Systems Using ILOM

Additional Reference

https://www.digitalocean.com/community/tutorials/how-to-use-systemctl-to-manage-systemd-services-and-units

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