[Glass] Backup procedure

[Trussardi Dario Romano via Glass]

Ciao, 

	very thanks....
	
>>        And if i right understand i can switch from master to slave in real time ( some minutes? ).
> 
> When you need to activate your slave, you
> 1. stop the logreceiver
> 2. SystemRepository commitRestore
> 
> This is really quick (a few seconds)
> 
> 3. Switch over your web server to talk to the slave. Here you may have
> to think a bit how you want to do it. If your web server is on master,
> you may have to do a DNS change (if the master machine is dead). If it
> is alive, you can route traffic to the slave using the firewall or
> some other way.

	Very well.

> 
>>        But it required some hardware and .... configuration.....
>> 
>>        I think to use it to very 24x7 maximum guarantee system and continuity of service.
> 
> Yes, I think it is a decent solution. There is no absolute guarantee
> though. You have to be sure that the logsender / receiver have caught
> up all the log entries and you may have switched over on a point where
> you lost a last transaction.
> 
>>        Restore the system to the last tranlog backup is not sufficient.
>> 
>>        As the customer can realign the system if the last backup tranlog is 30 minutes old?
> 
> I don't really get what you're saying here.

	Ok, excuse.

	I'm thinking about system without any standby system.
	
	But a system where i create a new tranlogs every 30 minutes and i save the old tranlogs on the backup system every 30 minutes.

	In this case on the backup system i have the last repository backup ( do every night ) and the relative old tranlogs  ( create in sequence every 30 minutes )

		but i don't have any "copy" of the current tranlogs.

	In this case if the master system go down i lose the last online tranlogs ( with the transactions relative to the current 30 minutes )

> If you have the tranlogs on master, then you can replay until the last
> transaction, when your system comes back up.
> If your tranlogs are lost on master but you restart with the existing
> extent(s), you may have lost transactions.
> If you have a hot standby in place, you are as up to date as you can
> be if you lose tranlogs on master.
> 
> If not losing tranlogs on master is really critical, I'll consider
> RAID and what other "safe" disk options you can get to store your
> tranlogs on. Gemstone also has a replicate tranlog directory which you
> can mount on a remote machine or something else.

	I don't know this options.

	It's a possible solutions ! ?

	The Gemstone replicate the online tranlogs in this directory on 'external' system ?

	If yes, i have a "copy" of the online tranlogs and i can restore from backup system to the last transaction.

	I don't find reference to this options  in the System Administration Guide 3.1.

> 
>>        Where i found the last 30 minutes transaction if the server is dead?
> 
> On the hot standby

	I write these considerations, thinking to a system without standby.

> 
>>        I think having an intermediate solution could resolve many situations.
>> 
>>        Having the ability to have a online copy of the active tranlog on the backup system it's a very good solution.
>> 
>>        Is possible use the logsender / logreceiver only to replicate the current logs on the backup system ?

	I need only to have the "copy" of the online tranlogs.
> 
> If I did run a hot standby, I do not worry about replicating tranlogs
> because this is what the logsender / receiver does
> 
>>        With this support and the last  production backup  it's possible restore the system without losing any transactions.
>> 
>>        But these are my considerations.....
>> 

	Thanks,  CIAO,

		Dario