Thanks. I will definitly have to read more about RM TF/SIM. There is no "hot backup mode" in sql server. I am looking to use TF/Clone to creat our reporting databases.

Looking through my RM logs I can see where the agent is talking to SQLServer agent within the instance hosting the database and freezes the database, peforms a consistent split of the clones, then thaws database. So this is scriptable, but it is most likely will require a bit of work.

Sql server's backups are always hot backups but unlike Oracle there is no such thing to put sql server database in "backup mode". thanks.

Like I said, I am no DBA so my terminology in reference to SQL backups may not be accurate. But I see in the logs that RM is able to freeze the SQL database for creating a consistent mirror/clone of the LUNs that the SQL data and log files use, and then RM issues a thaw command. Sounds like a backup mode to me .

I think the thing we need to focus on is that we all understand the reason why and how we need to get the db in a restartable mode, which is probably named differently in MS SQL or Oracle or DB2, or whatever.

Consistency and restartability is what we need here !

The magic is around behind RM's "freeze" and "thaw"   I am very sure there is no "backup mode" and no need for such thing in order to take a hot backup in sql server. thanks for sharing.

I will read more about RM. I have a feeling that RM might be doing something VDI which usually we don't deal with it when using sql server native backup. Not sure if RM is a seperate prodcut which doesn't come with the full package by default. Thanks again for sharing.

Izhu,

One thing you may want to try if you don't want to get into SQL scripting (RM is not do anything anyonelse with SQL and VDI scripting knowledge can't do)  is just a consistent split across all the LUNs that comprise the database. This will make the database crash consistent and SQL should be able to recover from that.

For example I replicate some very large OLTP SQL databases to our remote site using RecoverPoint. One of the databases is about 4TB is size and the data and log files are spread across 8 LUNs. RecoverPoint is not SQL or application aware and all I am able to do is create a write order consistent clone at the remote site. Even with such a large database the DBAs are able to bring the database online at the remote site using a crash consistent clone.

That's exactly what I try to understand. I've read a quite few docs from powerlink and not got very clear answer yet

Thanks very much the information. It is very helpful. We have similar needs and also need to "refresh/re-sync" daily for our reporting dbs which are copies of prod db.

Joe,

That is very cool, I did not know about this command. That is definitely a great option if you don't want the automation and job control that RM provides, or you don't want to spend the cash.

Izhu,

I just pulled this description out of the TimeFinder CLI Product Guide. This looks like what you were looking for and won't need RM is this works for you.

symioctl Sends I/O control commands to a specified server application.
  • Places objects into hot backup mode.
  • Freezes or thaws I/O to a specified database application.
  • Issues a checkpoint to the RDBMS.
  • Archives the current log.
  • Begins a Snap backup on SQLServer 2000 and higher.
  • Saves Snap meta data and resumes writes on SQLServer 2000 and higher.
  • Restores previously saved Snap meta data on SQLServer 2000 and higher.
  • Terminates the Snap operation without saving meta-data and resumes writes on
     SQLServer 2000 and higher.

Thank you Joe. This is great!  Do you know what doc in Powerlink has the details about these two magic commands "freeze" and "thaw"?

You do not need tsim to have a consistent SQL DB with TF clone,all you need is to quiesce your DB before the split using  symioctl which is part of tf base license.

I 've been using it for over 4 years now,basically you will issue the following command which does a DB freeze then checkpoint.

symioctl -type SQLServer freeze DBNAME -checkpoint -noprompt

You will split the devices at this point,verify the background split has completed then issue a DB thaw as follows.

symioctl -type SQLServer thaw DBNAME -noprompt.

You will need to setup your environment with some SET commands,if you need further assistance,let me know.

BTW I also use tsim for a different DB that requires SQL  log backups,tsim basically makes your TF synch\split SQL log aware.

Thanks very Aran!. With all you guys help I think I am on way to become SME in this area at our shop even though I am not the storage guy here

Here is the link to the TimeFinder CLI Product guide:

https://powerlink.emc.com/nsepn/webapps/btg548664833igtcuup4826/km/live1/en_US/Offering_Technical/Technical_Documentation/300-000-876_a13.pdf?mtcs=ZXZlbnRUeXBlPUttQ2xpY2tDb250ZW50RXZlbnQsZG9jdW1lbnRJZD0wOTAxNDA2NjgwNGUzMGZmLGRvY3VtZW50VHlwZT1wZGYsbmF2ZU5vZGU9MGIwMTQwNjY4MDRlMjY3MV9Hcmlk

And yes this forum will definitely put you on the path to being an SME in your environment. As you can see I learn something from this forum every day