Troubleshoot Management Agents Service

This section covers some typical issues and resolutions related to the Management Agents service, such as installing, and deinstalling with Management Agents and Management Gateways.

Topics:

Troubleshoot Management Agents Installation and Configuration Issues
Troubleshoot Management Agents Deinstallation Issues
- Error:… specifies multiple packages
- Error:… scriptlet failed with exit code
Troubleshoot Management Agents on Compute Instances
- Agent is in Not Available state and agent log file reports "Invalid tags"
Troubleshoot Management Gateways
- Remove Management Gateway
- Configure Management Gateway

Troubleshoot Management Agents Installation and Configuration Issues

Users may encounter various errors during Oracle Management Agent installation and configuration process. Causes and recommended actions for some common errors are listed below.

Please uninstall the agent and remove the service file before installing the new agent!

Cause: There's an agent already installed on your host. A previous deinstall process did not remove the agent service file successfully.

Action:

Run rpm -e oracle.mgmt_agent to uninstall the agent. If command succeeds, try installing the new agent. If command doesn't work, try the next recommended action.
Execute ls /opt/oracle/mgmt_agent to check if you have residuals of the previous agent installation. If you find it, delete it by running: rm -rf /opt/oracle/mgmt_agent.
Check if you already have agent service file at the following location depending on your Linux version:
- For OL7 (if you are using systemd): /etc/systemd/system/mgmt_agent.service
- For OL6 (if you are using init): /etc/init/mgmt_agent.conf.
  If you find that you have this service file, remove it by running: rm -rf /etc/init/mgmt_agent.conf and then retry installing the new agent.

Java is not a 64-bit JVM! Please set path of a 64-bit JVM in the environment variable JAVA_HOME or Java not found please set your preferred path in JAVA_HOME.

Cause: The JAVA_HOME environment variable is not set or it's not pointing to a 64 bit JDK location.

Action: Set JAVA_HOME environment variable to the right JDK version and retry installing the agent. Currently, only 64 bit JDK is supported.

Agent installation failed, please check log file.

Cause: The installation script cannot add a user and group during the management agent installation process because the available group ids on your Linux system are already in use.

Executing install
    Unpacking software zip
    Copying files to destination dir (/opt/oracle/mgmt_agent) 
useradd: Can't get unique GID (no more available GIDs) 
useradd: can't create group 
Agent installation failed, please check log file

Action: Consult with the system administrator before proceeding with the following:

Edit the /etc/login.defs file. You require sudo privileges to edit the file.
Look for the following entries:
```
SYS_GID_MIN               nnnn
SYS_GID_MAX               mmmm
SYS_UID_MIN               pppp
SYS_UID_MAX               qqqq
```
Where nnnn and pppp are the minimum value and mmmm and qqqq are the maximum value.
If the above entries don't exist in the file, add them.
Update the value of SYS_GID_MAX entry based on the system administrator's recommendation, and save the file.
Remove the failed agent installation by running: sudo rpm -e oracle.mgmt_agent.
Logout of the shell followed by login.
Retry the agent installation.

useradd: cannot create directory /usr/share/mgmt_agent

During the Management Agent installation, the mgmt_agent user is created with the default home directory location under /usr/share/mgmt_agent.

Cause: There's not enough file permissions under /usr/share or the file system is read-only.

Possible Actions:

Set file permissions to give mgmt_agent user access to the default user home directory location: /usr/share.
Set a different home directory location using the USER_HOME_DIR_ROOT environment variable if you want to use a different location.

Set the USER_HOME_DIR_ROOT environment variable with the path that you prefer to use as a home directory for mgmt_agent user, and ensure the management agent user has the right file permissions on that preferred directory.

Windows: The system cannot find the path specified. Agent install failed.

ERRORLEVEL=9009

Possible Cause: Environment variables have not been set properly due to spaces in the directory/folder name.

Windows environments allow to use spaces within a directory/folder name which causes an issue with the Management Agent installation since quotes are added to the name automatically by Windows. For example, there's a directory/folder named: Program Files. In this case Windows auto-inserts quotes since there's a space within the folder name, and it will now say: "Program Files".

Extra quotes can cause an issue since Management Agent installer does not allow quotes for environment variables like JAVA_HOME and AGENT_INSTALL_BASEDIR.

Note

The Management Agent installer does not accept the following special characters in the path: [, ^^, ", ', &, or ].

Action:

The recommended way to set up environment variables in Windows is by using the Advanced System Settings.

On the Windows taskbar, right-click the Windows icon and select System.
In the Settings window, under Related Settings, click Advanced system settings.
On the Advanced tab, click Environment Variables.
Click New to create a new environment variable. Click Edit to modify an existing environment variable.
After creating or modifying the environment variable, click Apply and then OK to have the change take effect.
Note

The graphical user interface for creating environment variables may vary slightly, depending on your version of Windows.

Management Agent status is "Not Available" in Console after the initial installation

Possible Causes:

(a) Missing policies

Action: Verify that the policies are added to Management Agent as described in the set up instructions. For details, see Set Up Oracle Cloud Infrastructure for Management Agent Service.

If the policies are missing, add them as described in Set Up Oracle Cloud Infrastructure for Management Agent Service.
(b) Typos in policies

Action: Review the policies syntax for any errors by comparing them against the policies samples. For details, see Set Up Oracle Cloud Infrastructure for Management Agent Service.

For example, ensure that the dynamic group definition is defined correctly as per the following syntax with right single quote characters around the compartment id and managementagent resource type:
```
ALL {resource.type='managementagent', resource.compartment.id='ocid1.compartment.oc1.examplecompartmentid'}
```
(c) Incorrect compartment id in Dynamic Group definition

Action: Verify that the install key compartment id is the same as the compartment id specified in the agent's dynamic group definition. By default the agent is created in the install key's compartment.
(d) Incorrect system timestamp

Action: Verify the system time of agent host, and correct it if it is not accurate.

Agent runs into OutOfMemoryException

Possible Cause: The agent might run out of heap memory if it is not tuned properly to support the load that has been assigned to it.

Action: Update the heap memory settings for the Management Agent.

The out-of-box configuration for the maximum heap for the agent is:

128 MB for Management Agent as an OCA Plugin.
512 MB for standalone Management Agent. (The one downloaded from Management Agent console).

The user can update and assign more heap to the agent by doing the following:

Open file: agent_inst/config/java.options.
Edit the above file. Update the heap setting by modifying the following line: -Xmx512m
For example: The above line sets the maximum heap for the agent to be 512 MB.

To change the heap to 800 MB update the above line to be: -Xmx800m
Save the file and restart the agent for the changes to take effect.

IP address being displayed in host column when Management Agent installed on Windows host

Problem: Management Agent is installed on a Windows host and the Management Agent console displays the IP address of the Windows host in the UI page instead of displaying fully qualified domain name (hostname) of the Windows host.

Action:

Login to Windows host and open the Control Panel.
Click System and Security and then click System.
Look for the Computer name, domain, and workgroup settings section and then click Change settings located on the right-hand side of this section.

The System Properties pop-up window is displayed.
By default, the Computer Name tab is selected. If it's not selected, then click Computer Name.
Look for the following message: To rename this computer or its domain or workgroup click Change.
Click Change.

A pop-up window named Computer Name/Domain Changes is displayed.
For example, if the FQDN of the Windows host is: FOOBAR004.subnet1ab2regsu.dummytenantreg1.abcvcn.com , provide the provide the short hostname of the Windows host: FOOBAR004 in the text box named Computer Name.
Click More and another pop-up window named DNS suffix and NetBIOS Computer Name is displayed.

In the text box named Primary DNS suffix of this computer, provide the DNS name of the Windows host.

For example: subnet1ab2regsu.dummytenantreg1.abcvcn.com
Click OK or Apply and close all the pop-up windows.
Restart the Windows host.
Uninstall the existing Management Agent by executing uninstaller.bat script from the Windows terminal.
Now install again install Management Agent on the Windows machine.

Management Agent installation should be successful and on the Agent UI page FQDN of the Windows host would be displayed in the host column

Management Agent installation fails on SELinux when using external volume

The agent service fails to start after executing the installation. This situation results in a non-working agent and display the following messages:

systemctl start mgmt_agent
Job for mgmt_agent.service failed because the control process exited with error code.
See "systemctl status mgmt_agent.service"and "journalctl -xeu mgmt_agent.service" for details.

To confirm, check the service manager logs for error details.

journalctl -xeu mgmt_agent.service
...
Dec 08 15:48:19 ol9-arm systemd[1261408]: mgmt_agent.service: Failed to execute /dir1/oracle/managementagent/agent_inst/bin/agentcore: Permission denied
Dec 08 15:48:19ol9-arm systemd[1261408]: mgmt_agent.service: Failed at step EXEC spawning /dir1/oracle/managementagent/agent_inst/bin/agentcore: Permission denied

Also, check the audit logs.

$ ausearch -ts recent -m avc -i
...
type=AVC msg=audit(12/08/202315:49:26.991:51338) : avc:  denied  { read open } for  pid=1261576comm=(gentcore) path=/dir1/oracle/managementagent/agent_inst/bin/agentcore dev="dm-0"ino=915154scontext=system_u:system_r:init_t:s0           tcontext=unconfined_u:object_r:default_t:s0 tclass=file permissive=0

All the above error messages indicate that your SELinux does not allow you to execute commands in the chosen folder.

Action: Contact your system administrator and create the required policies that allow installing and running the Management Agent.

Troubleshoot Management Agents Deinstallation Issues

This topic covers the typical issues and their resolutions related to deinstalling Oracle Management Agents.

Error:… specifies multiple packages

Cause: The rpm registry has multiple packages with that name.

Action: Use the --allmatches flag when running the rpm -e command:

rpm -e oracle.mgmt_agent --allmatches

Error:… scriptlet failed with exit code

Cause: The rpm could not stop the running agent or failed to remove the agent service file from the system.

Action: To resolve it, try the remove the agent manually.

Check if your agent is running:
For OL7: systemctl status mgmt_agent

For OL6: /sbin/initctl status mgmt_agent
If you see the agent is running, stop it:
For OL7: systemctl stop mgmt_agent

For OL6: /sbin/initctl stop mgmt_agent
Remove rpm by executing rpm -e oracle.mgmt_agent --noscripts. This command will skip all rpm scripts and try to remove the package from its registry.
Remove all the agent files by executing rm -rf /opt/oracle/mgmt_agent. Also run the following:
For OL7: rm -rf /etc/systemd/system/mgmt_agent.service

For OL6: rm -rf /etc/init/mgmt_agent.conf

Troubleshoot Management Agents on Compute Instances

Users may encounter various errors during the deployment of Oracle Management Agent on compute instances. Causes and recommended actions for some common errors are listed below.

Agent is in Not Available state and agent log file reports "Invalid tags"

The Management Agents page shows the Agent in 'Not available' state and the mgmt_agent.log file (located under <Agent_Inst>/logs directory) reports the following message:

ErrorBody:{"code" : "InvalidParameter","message" : "Invalid tags: Resource creation failed because the resource requires tag value(s). Add a value to the each of the following tag definition(s): \nGLOBAL.ComponentType, GLOBAL.ApplicationName,

Cause:

This issue can happen when the compartment requires mandatory tags for every resource and the resource creation request does not include the tags, then the activation request would fail with the message:"Invalid tags: Resource creation failed because the resource requires tag value(s)" and the agent status is shown as 'Not Available'.

Action:

Management Agents
If you have a standalone Management Agent, it must be uninstalled.

If the Management Agent was installed using an RPM or a ZIP file, it must be uninstalled and reinstalled by providing a response file using the DefinedTags parameter as described in the Review Agent Parameters section.
Management Agents on Compute Instances
If the Management Agent is enabled through the OCI Console using the OCA plugin, then there is no response file since it's not used for compute instances. In this case, do the following:
1. Login to the instance where the Management Agent is deployed and sudo as oracle-cloud-agent user using command:
```
sudo -u oracle-cloud-agent sh
```
2. Create agent.definedtags file under/var/lib/oracle-cloud-agent/plugins/oci-managementagent/polaris/agent_inst/config/security/resource/ directory.
3. Add defined tags needed for the resource to be created in agent.definedtags file.
  For example, you can add the following:
```
[{"GLOBAL":{"ComponentType":"<value>"}}, {"GLOBAL":{"ApplicationName":"<value>"}}]
```
4. Restart oracle-cloud-agent using the command:
```
sudo systemctl restart oracle-cloud-agent
```

Management Agent setup failed with fork/exec oracle.polaris.oca.main: permission denied

Users may encounter this error resulting in failure to install or start the Management Agent.

The error message shown in the Plugin view of compute instance for the Management Agent Plugin looks similar to the following:

workflow.go:23: [ERROR] step [*core.SetupImageStep] execution failed with [setup image failed with [fork/exec 230821.1905/bin/oracle.polaris.oca.main: permission denied]]
mgmtagent_image.go:139: [ERROR] bootstrap workflow failed with error setup image failed with [fork/exec 230821.1905/bin/oracle.polaris.oca.main: permission denied]
agent.go:74: [ERROR] failed to start agent during bootstrap with [setup image failed with [fork/exec 230821.1905/bin/oracle.polaris.oca.main: permission denied]]

Possible Cause:

This issue may happen when a compute instance disallows fork/execute operations from the /tmp directory by mounting the tmpfs with the noexec flag.

To confirm this possible cause, run the following:

$ mount | grep tmpfs
tmpfs on /tmp type tmpfs (rw,nosuid,nodev,noexec,inode64)

The output should say does have the noexec flag.

Action:

Stop Oracle Cloud Agent.
```
 sudo systemctl stop oracle-cloud-agent
```
Add the following setting to the file: /etc/oracle-cloud-agent/plugins/oci-managementagent/config.yml
```
overrideTmpDir: true
```

Start Oracle Cloud Agent.

$ sudo systemctl start oracle-cloud-agent

Troubleshoot Management Gateways

This topic covers typical issues and resolutions related to Management Gateways.

Remove Management Gateway

Cause: In some cases, it may be necessary to remove an existing Management Gateway installation, in order to reinstall it.

Action:

Check if the gateway is running:

For OL7: systemctl status mgmt_gateway

For OL6: /sbin/initctl status mgmt_gateway

If the gateway is running, stop it:

For OL7: systemctl stop mgmt_gateway

For OL6: /sbin/initctl stop mgmt_gateway
Remove the installed Gateway RPM using the following command: rpm -e oracle.mgmt_gateway --noscripts
Remove any remaining Gateway files using the following command:

rm -rf /opt/oracle/mgmt_agent
Run the following:

For OL7: rm -rf /etc/systemd/system/mgmt_gateway.service

For OL6: rm -rf /etc/init/mgmt_agent.conf

Configure Management Gateway

Cause: In some cases, the hostname might not be resolved in the installation environment which might cause the installation to fail with the following error message:

"Could not resolve hostname <hostname value> in the installation environment. Resolve the hostname or provide the GatewayCertCommonName in the response file and rerun the gateway setup script."

Action:

Check and resolve the hostname of the environment to get the fully qualified doamin name (FQDN) value after running the command: hostname -f
Optionally a user can provide a custom fully qualified domain name for the gateway configuration via seeding the GatewayCertCommonName property in input response file. See Response File Parmaters

Re-run the configure gateway script again.

sudo /opt/oracle/mgmt_agent/agent_inst/bin/setupGateway.sh opts=<user_home_directory>/gateway.rsp

Oracle Cloud Infrastructure Documentation

Troubleshoot Management Agents Installation and Configuration Issues

Troubleshoot Management Agents Deinstallation Issues

Troubleshoot Management Agents on Compute Instances

Troubleshoot Management Gateways