Re: CACHE BATT EXP 90 DAYS???

If your data is properly mirrored then a failure does NOT stop the system. A System i protected with RAID, no matter what it's value, does in fact stop if a controller fails. I would be read the EMC SAN documentation carefully because I suspect they maintain redundant paths to your DATA not necessarily multiple paths to the same physical disk unit. While the net effect of this to systems using such a SAN is no different the complexity and cost of such a setup is going to be higher than Mirroring on i5/OS. Plus it's another machine to maintain, from another vendor, and performance of SAN based disk solutions for System i must be carefully monitored or you can create I/O bottlenecks very very easily.

And of course that is why the 'assume' word is a bad one. You can build a system as small as a model 550 with redundant paths to all data. You can build a model 595 with no disk protection whatsoever. This is why the more important your data the more skilled you want the person who designs your system, no matter how large your system is, or isn't.

- Larry

Lukas Beeler wrote:

That's why I said "assume".

A colleague of mine works for EMC, and their enterprise SAN systems have
redundant access paths to all disks, and also redundant controllers. I
have assumed that a 595 is similar to an enterprise SAN when it comes to
storage architecture.

Or would the failure of a single RAID controller bring a system worth
multiple million dollars to its knees?