cancel
Showing results for 
Search instead for 
Did you mean: 

FastResync on Windows - does it track changes between regular mirrors?

Alistair_Veit1
Level 2

Hi,

Does FastResync in Storage Foundation for Windows 5.1 SP1 track the changes between regular mirrors in a volume (not snapshot mirrors)? My customer uses SFW to mirror large volumes between two data centres, and he wants a quick resync of these volumes if he has a temporary storage outage in one data centre.

I know this works in SF for Unix, but I've never tried this before in SFW.

Thanks, Alistair.

1 ACCEPTED SOLUTION

Accepted Solutions

RiaanBadenhorst
Moderator
Moderator
Partner    VIP    Accredited Certified

Hi,

 

You can enable FastResync for SFW volumes using vxvol set fastresync=on

 

You have to do it before the mirror is detached and it must remain on until its re-attached (so best to just leave it on)

 

When you enable FR it will create a DCO volume to keep track of the changes. Its a good idea to mirror the DCO as well.

 

So same as Unix really :)

View solution in original post

4 REPLIES 4

Marianne
Moderator
Moderator
Partner    VIP    Accredited Certified

Dirty Region Logging is used for regular mirrors. Simply right-click on the volume and select Log -> Add

Extract from Admin Guide:

When a dirty region log is created, a log subdisk is added to the volume. Multiple
logs can be associated with a single mirrored volume as a fault-tolerant measure.
Depending on the number of logs configured, this may result in degraded
performance.

RiaanBadenhorst
Moderator
Moderator
Partner    VIP    Accredited Certified

Hi,

 

You can enable FastResync for SFW volumes using vxvol set fastresync=on

 

You have to do it before the mirror is detached and it must remain on until its re-attached (so best to just leave it on)

 

When you enable FR it will create a DCO volume to keep track of the changes. Its a good idea to mirror the DCO as well.

 

So same as Unix really :)

Daniel_Schnack
Level 4
Employee Accredited Certified

You can enable FMR for a regular mirrored volume if you have the FlashSnap license (this option provides FMR functinality). If you do not have a FlashSnap license, you will only be able to use a DCO which will be used after system failures.

Marianne
Moderator
Moderator
Partner    VIP    Accredited Certified

DCO log is the Data Change Object that is created when FastResync (FlashSnap) is enabled on a volume.

DRL (Dirty Region Log) is the log that can be added to track changes on normal mirrors.