Installing the Management Agent on Oracle PCA

Before discovering the Oracle Private Cloud Appliance (PCA) in Enterprise Manager, you must first prepare the appliance and install a Management Agent. Follow the steps below to properly configure your Oracle PCA:

Change the oracle user password to a known password on both management nodes of the Oracle PCA Rack:
```
# passwd oracle
```
Verify the VIP and public Enterprise Manager IP are in the /etc/hosts file on both management nodes and on the Enterprise Manager Host:
```
YOUR.VIP vip-host1.example.com vca1-vip-vip
YOUR.EMIP  em-host1.example.com em01
```
On an the active management node, create an agent directory on the shared NFS directory. The shared nfs directory is required for both availability and failover purposes.
```
# mkdir /nfs/shared_storage/oemagent
# chown oracle:dba /nfs/shared_storage/oemagent
```
Note:
- By default, the Enterprise Manager agent port 3872 is pre-populated by Oracle PCA software. If you use this default Enterprise Manager agent port 3872 for pushing the agent, then this step is not needed.
- However, if the non-default port is used for Enterprise Manager agent, the steps do need to be executed on standby management node.
- If the agent port is different to the default port (3872), you must configure the firewall for that particular port, as 3872 is set by default in the Oracle PCA management node setup.

Open an Enterprise Manager agent port in the firewall by running the following command. Make sure you choose the same port while pushing the agent in step 5:

iptables -I INPUT <line_num> -m state --state NEW -m tcp -p tcp --dport <agent_port> -j ACCEPT
where line_num is any line number before the rule to block all traffic
# service iptables save
#service iptables reload

Push the Management Agent from the Oracle Management Server (OMS). From Enterprise Manager Cloud Control:
1. From the Setup menu, select Add Target, then select Add Targets Manually.
2. In the Add Host Targets area of the Add Targets Manually page, click Install Agent on Host. The Add Host wizard will begin.
3. Add a Host and Platform. On this page, click Add and select Manually. Enter a host name (fully qualified) in the Host field. This name should be the fully qualified virtual IP host name of the Oracle PCA rack for deploying the agent. Select Linux x86-64 from the Platform menu.
  
  Click Next.
4. On the Installation Details page, enter the following information:
  - Installation Base Directory: /nfs/shared_storage/oemagent
  - Instance Directory: /nfs/shared_storage/oemagent/agent_inst (This value is automatically completed based on the Installation Base Directory input.)
  - Named Credential: <agent_username>
    
    Note:
    
    If this is the first time you are adding a credential, an add icon () appears. Click this icon for a dialogue box that prompts for the credentials of the agent user (oracle/password for example).
    
    Create a Named Credential for the oracle user with the password you set in step 1 above.
    
    Once created, that credential and any other credentials that have already been added to Enterprise Manager will be available for selection. For an existing installation of an Enterprise Manager, a user may already have the necessary credentials available for selection for Oracle PCA discovery.
    
    This root privileges field is located in between Name credential and Privileged Delegation Setting in Enterprise Manager 13.3.
  - Privileged Delegation Setting: Leave the default. By default, this field is populated with /usr/bin/sudo -u %RUNAS% %COMMAND%
  - Port: By default, this field is populated with 3872. If you've not used the default port 3872, then ensure to specify the port number.
  - Preinstallation Script: Leave this field blank.
  - Postinstallation Script: Leave this field blank.
  - Additional Parameters: Leave this field blank.
  Once the fields are complete, click Next.
5. On the Review page, review the details of the host information. Click Deploy Agent.
  
  Note:
  
  During the agent install as a non privileged user, the user interface will display a warning and state that privilege scripts need to be run manually as the root user. Select Continue All Hosts and once the agent install has completed, run the following privileged scripts as the root user on the Oracle PCA active management node:
  
  /nfs/shared_storage/oemagent/agent_13.3.0.0.0/root.sh
  
  /u01/app/oraInventory/orainstRoot.sh
  
  For more information, see Meeting the Generic Prerequisites for Installing Standalone Management Agents Using Add Host Targets Wizard or EM CLI
On the active management node, set the emd property AgentListenOnAllNICs to false by running following command with the agent user (i.e., oracle):
```
/nfs/shared_storage/oemagent/agent_inst/bin/emctl setproperty agent -name "AgentListenOnAllNICs" -value "false"
```

Copy the following agent installation files to the passive management node (ovcamn06r1 is passive in this example):

# scp /etc/init.d/gcstartup root@ovcamn06r1:/etc/init.d/
# rsync -og /etc/oragchomelist root@ovcamn06r1:/etc/oragchomelist
# rsync -rog /u01/app/oraInventory/ oracle@ovcamn06r1:/u01/app/oraInventory/

On the active management node, remove all gc rc.d links (no startup of agent on startup):
```
# for x in `find /etc/rc.*/rc* | grep gcstart`; do rm $x; done
```

Restart the Enterprise Manager agent on the active management node as oracle from the agent's emctl command:

% /nfs/shared_storage/oemagent/agent_inst/bin/emctl stop agent
% /nfs/shared_storage/oemagent/agent_inst/bin/emctl start agent