Video Screencast Help

Global Cluster for SQL

Created: 17 Jul 2012 • Updated: 03 Aug 2012 | 4 comments
pgm10s's picture
This issue has been solved. See solution.

Hi

   We have 2 nodes  cluster as local HA  for SQL server. We would like to confiugre the Global Cluster using VVR for replication.

Now the database files are stored in 3 DG. Is it possible to configure the Global cluster using 3 DG. I only have configure the Global Cluster using only 1 DG for store the data.

Thank you.

Discussion Filed Under:

Comments 4 CommentsJump to latest comment

Wally_Heim's picture

Hi pgm10s,

Yes, you can have a GCO configuration with 3 diskgroups being replicated.  The bigger concern since you are using SQL is that SQL database and log files for a given database will need to be in the same diskgroup and same replication data set.  This is to ensure consistency between the database and SQL files.

If your current configuration does not have the SQL database and logs in the same diskgroup, then you can always use the Flashsnap option to join the diskgroups to a single diskgroup.

Thank you,

Wally

SOLUTION
pgm10s's picture

Thank you very much.

I think I must configure the 1 DG for GCO to ensure the data consistent.

mikebounds's picture

VCS can be configured with 3 DGs (this may be manually if wizard can't cope), but the problem is likely to be VVR.  The RVG you create for VVR is inside a diskgroup and therefore you would need 3 RVGs.  The volumes in each diskgroup will be consistent, but the 3 RVGs will not be consistent in async mode, meaning they are not guaranteed to be at the same point-in-time.  If the datafiles in the 3 diskgroups are from the same SQL instance then the datafiles MUST be at the same point-in-time for the data to be consistent.   This MAY work if you have 3 separate databases, each in its own diskgroup, but even then it depends on whether the 3 databases need to be in sync with each other.

Best option is to join the diskgroups which you can do in VEA or using "vxdg join" CLI if you have an Enterprise licence (SFW Enterprise licence, not SFW for MS Enterprise Windows).

See posts https://www-secure.symantec.com/connect/forums/where-can-i-verify-consistent-data-under-vvr and https://www-secure.symantec.com/connect/forums/one-rvg-going-constant-behind-and-dont-get-max-bandwidth-replicate-data-100 for more info on consistent data with databases.

Mike

UK Symantec Consultant in VCS, GCO, SF, VVR, VxAT on Solaris, AIX, HP-ux, Linux & Windows

If this post has answered your question then please click on "Mark as solution" link below

pgm10s's picture

Thank you very much. I think

Thank you very much.

I think I must configure the 1 DG for GCO to ensure the data consistent.