I was setting up a central logging host. I created a Volume through our EqualLogic SAN of 100GB with thin provisioning. Then created a virtual host through VMware and gave it the entire 100GB of space for the disk.
I had a configuration error that caused my log files to grow to the entire 100GB over night. So my disk was now very close to 100% used. According to these helpful links: http://communities.vmware.com/thread/255173 and http://www.equallogic.com/resourcecenter/assetview.aspx?id=5245
A thin-provisioned volume grows automatically due to application data writes. If later the application frees up space, the space is free in the file system but is not returned to the free space in the PS Series pool. The only way to reduce the physical allocation is to create a new volume, copy the application data from the old volume to the new, and then delete the old volume.
o Example: A file share is thin-provisioned with 1 TB logical size. Data is placed into the volume so that the physical allocation grows to 500 GB. Files are deleted from the file system, reducing the reported file system in use to 100 GB. The remaining 400 GB of physical storage remains allocated to this volume in the SAN.
o This issue can also occur with maintenance operations including defragmentation, database re-organization, and other application operations.
So to get around my EqualLogic storage warnings and alarms, I increased the size of my volume to 125GB. Now I needed to tell VMware about the change in the VMFS size. I fired up my VMware vSphere client and browsed one of my ESX servers in our cluster. Some instructions taken from here: http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1003302
- Powered off the virtual host.
- Click on the “Configuration” tab and selected the “Storage” link.
- Right click the Volume you would like to edit.
- You will see the device size listed and the VMFS size listed. Select the “Increase …” button.
- This will open a pop up wizard to add an extent to the VMFS file system.
- Follow the prompts for the Add Extent wizard to add an extent.
- Perform a rescan on every ESX host that is being presented the new LUN so that the additional of the extent is detected.
- Selected the virtual host and edited the hard disk size to the increased 25GB size.