ASM - number of LUNS rule of thumb
Date: Wed, 11 Aug 2010 16:13:24 +0100
I wanted to ask the list some advice on a particular ASM "rule-of-thumb" and advice on diskgroups per host.
We have recently decided upon using ASM, yes I know late to the party, we have studied quite a few white papers and they often suggest that you start somewhere between 4 to 8 luns maximum per diskgroup as a rule-of-thumb. I don't like rules-of-thumb, they suggest that no-one has any idea and it's a best guess! What do others have as a starting point basis for the number of raw luns under each diskgroup and why that number? I appreciate there are many more factors involved and we are slowly working through lots of these, but I am trying to get some facts based on experience, rather than simply taking documented suggestions as gospel truth.
Additionally, my colleague and I are arguing over the merits of the number of diskgroups per host. Say you have 4 instances on a host, does each instance have at least two diskgroup each ( DATA+FRA for example) , or do you simply make big diskgroup and throw all the instances into it? The "all-in-one" options suggest 'eggs-in-one-basket to me though.
Any advice from your vast collective experience on these two points, would be greatly appreciated.
Rgds George Johnson
Please consider the environment before printing
This message contains confidential information and is intended only for the individual or entity named. If you are not the named addressee you should not disseminate, distribute or copy this email. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. E-mail transmission cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore does not accept liability for any errors or omissions in the contents of this message which arise as a result of e-mail transmission. If verification is required please request a hard-copy version. This message is provided for informational purposes and should not be construed as an invitation or offer to buy or sell any securities or related financial instruments. GAM operates in many jurisdictions and is regulated or licensed in those jurisdictions as required. To the extent this email has been sent to you by any GAM company domiciled in the EU, being GAM (U.K.) Limited, GAM Sterling Management Limited, GAM International Management Limited, GAM London Limited, GAM Fund Management Limited, or GAM Fonds Marketing GmbH i.L., please note the following details in respect of each such company: - GAM (U.K.) Limited (a company limited by shares and registered in England and Wales with company number 01664573); - GAM Sterling Management Limited (a company limited by shares and registered in England and Wales with company number 01750352); - GAM International Management Limited (a company limited by shares and registered in England and Wales with company number 01802911); - GAM London Limited (a company limited by shares and registered in England and Wales with company number with Company Number 00874802) Each of Registered Office: 12 St. James's Place, London, SW1A 1NX GAM Sterling Management Limited, GAM International Management Limited and GAM London Limited are each authorised and regulated by the Financial Services Authority. GAM Fund Management Limited (a company limited by shares and registered in Ireland with no. 156828) of Registered Office: George's Court 54-62 Townsend Street Dublin 2, Ireland. Received on Wed Aug 11 2010 - 10:13:24 CDT