In a roundabout way, that's what I'm trying to get to. I realize there are hardware solutions that do the same; they replicate writes (really they bifurcate the write to disk) so you can have geoclustering solutions. But I'm trying to figure out how these bright programmers figured out a way to protect the application data and provide a six second failover. I'm concerned that such a solution would be a "poor man's" cluster at best, and a data integrity nightmare at worst. I don't see how the fast failover claim can work with the application nor how it is better than the MCS solution offered by the vendor of the application (concern for the third-party support comes into play here), but I have an open mind and if progress has been made, I'd like to educate myself on it. So far I don't see how the solution could be better, but I'm certainly interested to hear. _____ From: paul_lemonidis@xxxxxxxxxxx [mailto:paul_lemonidis@xxxxxxxxxxx] Sent: Tuesday, March 09, 2004 11:21 AM To: [ExchangeList] Subject: [exchangelist] RE: Exchange Server Redundancy http://www.MSExchange.org/ Hi all Sorry if I am missing something here but since when is a pure software solution that replicates an entire drive going to offer perforamnce anywhere near that of a cluster using shared drives. This seems nothing more than a co-standby server solution like say Vinca? Rather than a single shared drive it runs huge amounts of replciation between dupliacte drives on duplicate servers. I can actually see you paying more for an inferior solution from what I have seen so far. Hardware clustering is far more resilient if done correctly but it does come at a price, of course. At the end of the day you get what you pay for. Regards, Paul Lemonidis. ----- Original Message ----- From: Mulnick, <mailto:Al.Mulnick@xxxxxxxxxx> Al To: [ExchangeList] <mailto:exchangelist@xxxxxxxxxxxxx> Sent: Tuesday, March 09, 2004 3:23 PM Subject: [exchangelist] RE: Exchange Server Redundancy http://www.MSExchange.org/ <http://www.MSExchange.org/> I never considered MCS to be more difficult than adding a third-party app. Is that all it does? How does it make the recovery so fast? How does it check for db consistency? _____ From: Tiago de Aviz [mailto:Tiago@xxxxxxxxxxxxxxx] Sent: Tuesday, March 09, 2004 9:17 AM To: [ExchangeList] Subject: [exchangelist] RE: Exchange Server Redundancy http://www.MSExchange.org/ It is much simpler because it can be implemented on a single day, it replicates data on the bit level, it's a cheap software, and if you want, you can user a slower machine or any other machine for redundancy. No, while Brightstor is replicating, it doesn't know if the file is a database or a Star Wars movie. It's all the same for him. Tiago de Aviz SoftSell (41) 340-2363 www.softsell.com.br <http://www.softsell.com.br/> Esta mensagem, incluindo seus anexos, tem caráter confidencial e seu conteúdo é restrito ao destinatário da mensagem. Caso você tenha recebido esta mensagem por engano, queira por favor retorná-la ao destinatário e apagá-la de seus arquivos. Qualquer uso não autorizado, replicação ou disseminação desta mensagem ou parte dela é expressamente proibido. A SoftSell não é responsável pelo conteúdo ou a veracidade desta informação. _____