2 Replies Latest reply: Apr 9, 2013 7:19 AM by 1001926 RSS

    Disk usage information mismatch

      Hi All,
      I have probably a rather simple querry.
      I have a OVM 3.2.1 setup, where storage reposiroties are created on FC SAN LUNs. Everything works fine, however what I ahve noticed is, when I check disk usage with df -kh on OVM server cli, it shows

      */dev/mapper/36006016045002b0040a788bee38be211 400G 221G 180G 56% /OVS/Repositories/0004fb0000030000d6f553775a89a4d1*

      However when I look at the information for the repository hosted on this LUN via the OVM Manager repostories tab in the information pane on the right hand side I see

      File System:     Unmanaged FibreChannel Storage Array:/dev/mapper/36006016045002b0040a788bee38be211
      Share Path:     
      File System Size (GiB):     400.0
      File System Used (GiB):     196.65
      Used %:     49%
      ID:     0004fb0000030000d6f553775a89a4d1
      and this is the case with othere LUNs as well.

      As you can see that df reports almost 25GB more then the OVM Manager, and I am at loss as to why this difference?
      I would be greatful if someone out there could explain.


      Edited by: 998923 on 09-Apr-2013 02:50
        • 1. Re: Disk usage information mismatch
          Do you have any clones or created any vms from templates? I think the newer version is doing reflinks as follows:

          • 2. Re: Disk usage information mismatch
            Thanks for responding mate, I do have vms created from templates however I don't think it's reflinks as we are creating Non-Sparse vms and even if it is then I would expect to see same usage information from df and via the OVM manager GUI.
            My theory so far points towards the space required for the filesystem metadata etc for OFCS2, df shows usage including that and OVM manager shows usage minus the space taken up by the metadata, the only thing going against that is about 25 GB for metadata on a 400GB LUN doesn't look right and I ahve no way to check the basis of calculation done by OVM manager.