Changing the logging level for the VMware High Availability management agent (FDM) in vCenter Server 5.x (2004540)

Purpose

Increasing the logging level is helpful when troubleshooting VMware High Availability (HA) issues. This article provides steps to increase the amount of information logged by the vSphere 5 HA agent, called the Fault Domain Manager (FDM).

For more information about changing the logging level in earlier versions of Virtual Center and vCenter Server, see Enabling verbose logging for the VMware High Availability agent on ESX/ESXi hosts (1031247).

Note: This article is intended to assist you in troubleshooting HA issues in concert with VMware Support. VMware recommends only changing your logging level at the express request of VMware Support.

Resolution

The logging level can be set at either the cluster level or the host level:

• Changing FDM logging for a cluster
• Changing FDM logging for a host

Be sure to revert to the default logging level after the troubleshooting is complete. Detailed logging causes log files to be filed more quickly, and to rotate more quickly, so that retained logs show a shorter period of time. Depending on the issue, you may also want to increase the number of logs in a rotation. For more information, see the Log Files section of the vSphere High Availability Deployment Best Practices.

Changing FDM logging for a cluster

To change the logging level for FDM logs at the cluster level, use the HA advanced options in vCenter Server.

To change FDM logging at the cluster level:

1. In vCenter Server, right-click the cluster for which you need to change the settings. Select Edit settings.
2. Select vSphere HA, then click Advanced Options.
3. Click under Option, and add this:
   
   das.config.log.level
   
4. Click under Value, and add this:
   
   trivia
   
   Note: The default logging level is verbose.
   
5. (Optional) To increase the number of logs per rotation:
   
   
   1. Click under Option, and add this:
      
      das.config.log.maxFileNum
      
   2. Click under Value, and add this:
      
      15 
      
      Note: The value provided here is an increase of 50% over the defaul tnumber of logs per rotation, 10. The exact value you should use depends on your situation. For more information, see the Providing Sufficient Space for System Logging section of the vSphere Installation and Setup guide. 
      
6. Click OK, twice.
7. Run HA reconfig, for the change(s) to take effect:
   
   
   1. In vCenter Server, open the cluster-host list view
   2. Select all hosts.
   3. Click Reconfigure HA.

Changing FDM logging for a host

To increase the number of logs per rotation and the size of the log before it rotates using esxcli:

1. Open an SSH session to the ESXi host. For more information, see Using Tech Support Mode in ESXi 4.1 and ESXi 5.x (1017910)
2. Run esxcli system syslog config logger set --id=fdm --rotate=15 --size=10240
3. Run esxcli system syslog reload to apply the new configuration changes.

To change the logging level for FDM logs at the host level, edit the the fdm.cfg configuration file. By default, the fdm.cfg file is located at/etc/opt/vmware/fdm/.

To change FDM logging at the host level:

1. Back up the original fdm.cfg file. 
   
   Note: Do not skip this step. 
   
2. Open the fdm.cfg file using a text editor.
3. Locate the <log> tag within the file.
4. Change this entry:
   
<log>
  ...
  <level>verbose</level>
  ...
</log>
   
   To:
   
   <log>
  ... 
  <level>trivia</level>
  ...
</log>
5. (Optional) To increase the number of logs per rotation:
   
   
   1. Locate the <log> tag within the file. 
   2. Change this entry:
      
      <log>
      ...
      <maxFileNum>10</maxFileNum>
      ...
      </log>
      To:
      
<log>
  ...
  <maxFileNum>15</maxFileNum>
  ...
</log>
      Note: The value provided here is an increase of 50% over the defaul tnumber of logs per rotation. The exact value that you specify depends on your situation. For more information, see the Providing Sufficient Space for System Logging section of thevSphere Installation and Setup guide. 
      
6. Run HA reconfig, for the change(s) to take effect:
   
   
   1. In vCenter Server, open the cluster-host list view
   2. Select the host(s) for which you've changed the FDM settings.
   3. Click Reconfigure HA.

Source:-
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2004540