Issued: Error! Unknown document property name. iii Ron Hawkins wrote:
Seeing as the USP-VM does not support SAS drives, it is more likely that they are considering SAS drives that are installed in a HDS or other vendor's Storage Controller. In that case the performance of IO that goes past USP-VM cache to the external storage will largely depend on the design and architecture of that controller, and not just whether it is SAS, FCAL or SATA. You are right, Ron. Turns out it would be a HDS AMS2500 with Ultrastar 15K600 disk that would be virtualised SAS disk storage under the USP-VM. The specs certainly read well in comparison to our current IBM DS6800. Call me a nervous Nellie or what have you, but seeing how nobody else here in Australia is supposedly using SAS disk for the mainframe, I still have the following concerns... - will it support the required number of logical paths for 20 odd LPAR's? - could mainframe performance be degraded significantly by load on the open systems disk, that would make up the majority of data stored on the AMS2500? - Can the mainframe DASD part of the storage be isolated from those "whoops, I formatted the wrong disk" type actions against open systems disk? - Can it do custom volume sizes for DASD? - Will it work to mirror to a second DR site? Any distance limitations? - How long does the battery backup for the cache hold the data not yet destaged to disk for? - After total power failure, how long does it take for the AMS2500 and USP-VM to become operational again? Thanks in advance for your help. Sorry for all the questions! Regards, Fred Schmidt NT Government, Australia ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
