vCenter has 4 Storage Filters: –
- RDM Filter
- VMFS Filter
- Host Rescan Filter
- Same Host Transports Filter
These filters affect the actions vCenter takes when scanning storage as follows:-
RDM Filter
When you attempt to add a RDM to a VM the RDM filter filters out any RDM that have already been added to a VM leaving only the ones the LUNs that are not currently formatted as a datastore or attached to a VM as a RDM. By disabling this filter you can add the same RDM to multiple VMs.
VMFS Filter
When you use the Add Storage Wizard to add a VMFS volume to an ESXi host then the VMFS Filter filters out LUNs that have already been formatted as a VMFS datastore.
Host Rescan Filter
When you add a VMFS datastores to one ESXi host the Host Rescan Filter triggers all of the other ESXi hosts to rescan for the new volume. Disabling this filter prevents the other hosts doing this. This may be helpful when adding large amounts of VMFS datastores to a cluster, i.e. you can add all the new datastores to one ESXi host, maybe via PowerCLI, and then once completes get each of the other ESXi hosts to perform a rescan.
Same Host and Transports Filter
The Same Host and Transport Filter filters out LUNs that cannot be used to extend a VMFS datastore due to host or storage incompatibility, for example if the LUN is not presented to all hosts using the datastore.
By default all of the filters are enabled. To disable a filter you need to add the relevant advanced setting to vCenter (Administration….vCenter Settings….Advanced Settings) and set it to FALSE. By default these settings are not listed in the Advanced Setting, therefore to disable any of them you need to add them. The relevant settings are: –
| Filter | Advanced Setting |
| RDM Filter | config.vpxd.filter.rdmFilter |
| VMFS Filter | config.vpxd.filter.vmfsFilter |
| Host Rescan Filter | config.vpxd.filter.hostRescanFilter |
| Sam Host and Transports Filter | config.vpxd.filter.SameHostAndTransportsFilter |