Troubleshooting missing relationships

You must use the troubleshooting tips provided in the following sections to resolve issues of missing relationships between hosts and virtual machines, and between hosts and network devices.

Missing relationships between hosts and virtual machines

When you discover virtual hosts and ESX servers, and also when managing vCenters, the relationship between the host and virtual machine may be missing at times. You must use the troubleshooting steps described in this section to either resolve the problem or create a BMC Support case. 

Issue symptoms 

• vCenters servers and ESX servers are discovered successfully

• User can see the list of virtual machines

• Virtual hosts are discovered successfully

However, one or more virtual hosts are missing relationships with their ESX servers. Virtual host, ESX servers, and managing vCenters can be searched successfully in discovery.

Resolution

Perform the following steps to troubleshoot the missing relationships:

Step 1: Verify the discovery of attribute

If no relationship is created between an ESX server and virtual hosts, check if the serial number and UUID are discovered for the virtual hosts. If these are not discovered, proceed with the next step.

Step 2: Discover the serial number and UUID discovery of attribute

Check if the virtual hosts were scanned with sufficient permissions.

For example, on a Linux host if they are missing it is probably because the BMC Helix Discovery user does not have the permission to run the dmidecode command.

Connect to the server through SSH as the BMC Helix Discovery user and run these commands manually:

sudo /usr/sbin/dmidecode | grep "UUID"
sudo /usr/sbin/dmidecode | grep "Serial Number"

Now check if the serial number and UUID are reported. If not, ask your server team to provide the required dmidecode permission for the BMC Helix Discovery user. This should resolve the issue.

It may be necessary to configure sudo to run dmidecode and retrieve a serial number. For more information, see Adding privileged execution to commands.

f the problem persists, collect the discovery, model and reasoning logs in debug mode. Review the logs to try to identify error messages. You can also contact Customer Support and provide the results to all the questions and checks performed earlier.

Missing relationships between hosts and network devices

When you discover the host, switch however the relationships between host and switch is missing, use this section to obtain the appropriate logging and troubleshooting steps to either resolve the problem or create a BMC Support case.

Issue symptoms

• The host is discovered successfully. Similarly, the switch device is a supported device and is discovered successfully.
• However, the relationship between the host and the switch is missing.

Issue scope

You have confirmation from your network team that the switch and the host are directly and physically connected.

Resolution

Perform the following steps to troubleshoot the missing relationship:

Step 1: Verify if edge connectivity is enabled.

1. From the main menu, click the Administration icon.
   The Administration page is displayed.
2. In the Discovery section, click Discovery Configuration.
   By default, edge connectivity is enabled. If you do not intend to use the connection information obtained by edge connectivity, you can disable it. Disabling edge connectivity avoids any additional load onto switches in your infrastructure. To do this, an additional option, Discover neighbor information when scanning network devices, is available. This option controls whether the information on neighboring ports is obtained.
   • Select Yes to retrieve neighbor MAC addresses (enables edge connectivity).
   • Select No if you do not want to retrieve neighbor MAC addresses (disables edge connectivity).

Note that if you disable edge connectivity, all existing connections are deleted at the time of the next scan.

Step 2: Check the order of scan
The switch must be scanned before scanning the host. If you are not sure which one was discovered first, try scanning the switch and the host at least twice more.

Step 3: Check the MAC address of the host

Verify that BMC Helix Discovery has found a valid MAC address for the host in question. Run the following query to check the discovered MAC addresses of the host:

search Host where name has subword '<host_NAME>' show name, __all_mac_addrs as 'All Mac Addrs'

where, <host_NAME> must be replaced with the actual host name.

If the MAC address is missing, you need to first fix this issue and try to scan the switch and the host at least twice more.

For more information, see Capturing SNMP devices and this  article  on Communities. 

However, if the problem persists, collect the record data for host and switch logs with device capture of the switch. Contact Customer Support and provide the results to all the questions and checks described earlier.