Matt, Can you share more about the distance and SAN infrastructure that TSM I/O travels through? Many answers would be depending on them. As we know, TSM DB mirroring is at the SW level after OS or HW. First, try to avoid the redundant mirroring at TSM application with OS or HW since you concern about the latency. Also, when you said 'remote SAN devices', I assume you plan to use more than one disk subsystems. If so, instead of configuring mirror volumes at LUN level, you may consider it at the controller level such as remote mirroring with EMC, FAStT, ESS or SVC. Usually, in a FC SAN you don't have much latency among devices with 2Gb/4Gb interfaces. Especially, TSM write I/Os will be acknowleged at the cache level than the actual disk level, which minimize the possible latency. Be careful with your SW mirroring policy that potencially adds I/O overhead. You can achieve the data or LUN protection at various levels today, but considering the advancement in HW technology including FC/IP SAN, there are more options for TSM admins to get even better protection without affecting app's performance. Trying to come up wit at lease a dozen of recovery scenario with your existing system, will always help with better designing TSM with SAN for any DR situation. Gus
>>> [EMAIL PROTECTED] 07/13/05 11:52 AM >>> Hi *SM'ers, We are looking into the possibility of placing TSM DB mirror volumes on remote SAN devices. Has anyone already done this, and have any gotchas or issues? My first concern would be latency, but With mirrorwrite sequential it seems from the explanation that the primary mirror volume is the one that would be hurt by latency, not the secondary mirror volume. Would that be the case? Or, will TSM wait for the secondary mirror write to finish before embarking on the next primary mirror write on that DB volume? Matt. [EMAIL PROTECTED] [EMAIL PROTECTED] http://tsmwiki.ciom/tsmwiki/MatthewWarren Computer says 'No'.. ___________________________ Disclaimer Notice __________________________ This message and any attachments are confidential and should only be read by those to whom they are addressed. If you are not the intended recipient, please contact us, delete the message from your computer and destroy any copies. Any distribution or copying without our prior permission is prohibited. Internet communications are not always secure and therefore Powergen Retail Limited does not accept legal responsibility for this message. The recipient is responsible for verifying its authenticity before acting on the contents. Any views or opinions presented are solely those of the author and do not necessarily represent those of Powergen Retail Limited. Powergen Retail Ltd is authorised and regulated by the Financial Services Authority for the sale and service of general insurance products. Registered addresses: Powergen Retail Limited, Westwood Way, Westwood Business Park, Coventry, CV4 8LG. Registered in England and Wales No: 3407430 Telephone +44 (0) 2476 42 4000 Fax +44 (0) 2476 42 5432