The approach I used worked very well. I counted all of the tapes that would be kept on the VTL and multiplied that by the capacity of the tapes. I then calculated the growth rate of the tape pool and added that to the total, in my case 6 months out. That is the number I used. The assumption is that compression will be similar on both.
If you calculate off of occupancy there is a greater uncertainty because you do not really know how much compression you will get. Calculating off of tape counts will be inaccurate because of filling tapes, but this error is in the admins favor. Filling tapes can be factored in to reduce the error. Andy Huebner -----Original Message----- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf Of William Boyer Sent: Thursday, June 21, 2007 1:03 PM To: [email protected] Subject: [ADSM-L] Somewhat OT: Sizing a VTL solution Has anyone just gone through sizing a VTL solution for a library replacement? Is it as simple as taking your current occupancy/retention, applying for some compression and using that figure for the amount of storage behind the VTL? Or maybe I'm just trying to make something harder than it is. Wouldn't be the first time! :-) TIA. Bill Boyer >Select * from USERS where CLUE>0 0 rows returned This e-mail (including any attachments) is confidential and may be legally privileged. If you are not an intended recipient or an authorized representative of an intended recipient, you are prohibited from using, copying or distributing the information in this e-mail or its attachments. If you have received this e-mail in error, please notify the sender immediately by return e-mail and delete all copies of this message and any attachments. Thank you.
