Forum Discussion

eu22106's avatar
eu22106
Level 4
12 years ago

Rescan takes 10 minutes

Hi all, I was wondering what the experience is about the duration of a rescan. In my environment (W2K3 SFWHA5.1 SP2 80 lun's) a rescan takes up to 10 minutes which I think is a very long time. Or a...
business continuity
Performance
Storage Foundation for Windows
  • Wally_Heim's avatar
    Wally_Heim
    12 years ago

    Hi eu22106,

    10 minutes can be a long time.  I've seem some customers in the 45 minute timeframe.  It is all relative to what you as the customer see as a problem.  If you are already running CP10 then you have the performance improvements to the rescan that I was mentioning.

    The rescan time also extends the time needed for boot.  A few things that I can recommend since you are running windows 2003, is to make sure that you check or update the following:

    1. HBA firmware and drivers (hardware specific)

    2. Storport.sys (Microsoft)

    3. Mount manager drivers (Mircrosoft.)

    4. The latest DDI package for 5.1 SP2.  This is a DMP/DSM update. (Symantec)

    From there, if things are not improved, it might take more drastic configuration changes.  These are a few more drastic items to check.

    1. As a simple configuration test, you could drop down to 4 paths per lun (or fewer) to see if the rescan times increase. 

    2. Decrease the number of luns presented by presenting larger luns.  This will take some  planning as your existing volumes will need to be mirrored to the new larger luns.  The downfall here is depending on how you are using the existing luns, it might be hard or impossible to change to larger lun sizes.

    Thank you,

    Wally

Wally_Heim's avatar
Wally_Heim
Level 6
12 years ago

Hi eu22106,

10 minutes can be a long time.  I've seem some customers in the 45 minute timeframe.  It is all relative to what you as the customer see as a problem.  If you are already running CP10 then you have the performance improvements to the rescan that I was mentioning.

The rescan time also extends the time needed for boot.  A few things that I can recommend since you are running windows 2003, is to make sure that you check or update the following:

1. HBA firmware and drivers (hardware specific)

2. Storport.sys (Microsoft)

3. Mount manager drivers (Mircrosoft.)

4. The latest DDI package for 5.1 SP2.  This is a DMP/DSM update. (Symantec)

From there, if things are not improved, it might take more drastic configuration changes.  These are a few more drastic items to check.

1. As a simple configuration test, you could drop down to 4 paths per lun (or fewer) to see if the rescan times increase. 

2. Decrease the number of luns presented by presenting larger luns.  This will take some  planning as your existing volumes will need to be mirrored to the new larger luns.  The downfall here is depending on how you are using the existing luns, it might be hard or impossible to change to larger lun sizes.

Thank you,

Wally