Oracle 10g RAC and ASM - high availability

[daljitsb]

Environment: Oracle 10.2 (Standard edition)
Windows 2003 server connected to SAN

We will have about 15-20 different databases running through 1-2 windows oracle servers. The purpose is to have high availability and quick failover.

1. Can we use RAC without using ASM. How easy/tough it is going to be managing/using RAC without ASM.

2. If possible should we use Oracle 64 bit with Windows 64 bit OS.

Please advice.

Thanks

-D

[pando]

you can only use ASM with standard edition

running 15 instances in RAC does not make sense why not consolidate them?

[KenEwald]

you can only use ASM with standard edition

Huh?

[pando]

RAC Standard --> ASM

[KenEwald]

RAC Standard --> ASM

"Standard" being the minimum and including Enterprise edition.

Here's an Oracle CYA recommendation: 1/2 as many databases in your clustered environment as you have cpu's for LMS block caching.

I have a 2 node RAC (2 dual core cpu's on each node) running 19 databases. Memory is an obvious issue. Occasionally we get an issue with "Global Cache Blocks Lost" in this environment.

ASM has some really cool features and some very cool undocumented features we'll probably all learn about in future releases. We adopted it early and have been very pleased with it's performance ease of managment. Makes striping a no-brainer and moving disks around is a piece of cake.

As always, Oracle is a general purpose RDBMS and you are well advised to test your environment thoroughly.

[Bore]

Yes, I belive PANDO is right. Just do not know if it is a technological limit or a licence limit
Besides, I do not see what's wrong with ASM and why should we try to avoid using it

[daljitsb]

Yes, I belive PANDO is right. Just do not know if it is a technological limit or a licence limit
Besides, I do not see what's wrong with ASM and why should we try to avoid using it

We do need to keep 15 db seperate.

So are you saying, ASM is a proven technology with all posotive benefits and should always be employed?

The reason for avoiding ASM is to be able to continue working with file system and not raw disks - our current much needed tool used by many here works with file system. The tool drops and adds schemas and tablespaces on daily basis.

I am still looking for clear answers to:

1. Can we (should we) use RAC without using ASM.
2. Should we use ASM without using RAC.
3. How easy/tough it is going to be managing/using RAC without ASM.
4. If possible should we use Oracle 64 bit with Windows 64 bit OS.

Please advice

-D

[PAVB]

So are you saying, ASM is a proven technology with all posotive benefits and should always be employed?

Yes it is.
Easy to use, near raw-device performance... what else would you ask for?
ASM is so good Oracle is building an O/S around it.

[pando]

We do need to keep 15 db seperate.
I am still looking for clear answers to:

1. Can we (should we) use RAC without using ASM.
2. Should we use ASM without using RAC.
3. How easy/tough it is going to be managing/using RAC without ASM.
4. If possible should we use Oracle 64 bit with Windows 64 bit OS.

Please advice

-D

1. You can but with standard edition which you are going to buy ASM is your ONLY choice
2. Up to you, it's a proven technology & used in multi terabyte customers
3. If you use CFS then it's just like any other files
4. Up to you again, 32 bit cannot fit > 3GB SGA whereas 64bit can. Nowdays however one would always consider 64 bit. There arent much compatibility problems as before.

Regarding having 15 DB:

I have a customer who used to run 200 databases, they were like you, saying they cannot merge in less databases but they understood the idea and the concepts. Now days they run 15 databases instead of 200 in HA environment with Data Guard.

[Bore]

Well,
I am affraid that if u use RAC, file system is not an option at all (except if you do not use OCFS)

For RAC you'll need either ASM or raw partitions, because the disks should be mounted by all the instances at the same time, which I am affraid is not possible with most file systems.
About the ASM, I have some customers in the banking sector, running RAC on ASM. Is that good enough for you?

Regards
Boris