All of which are accounted for by having two or more of these, combined with the feature they call (I'm not kidding) Geographically Dispersed Parallel Sysplex (GDPS).
You can hook up multiple IBM mainframes remotely and set them up to automatically ensure consistent replication of machine state to various extents depending on your reliability vs. performance tradeoffs and replication distance (latency being the issue), all the way up to active-active operation across systems.
So in other words: It works far better than the failover options most people deploy on their off the shelf servers in their self-wired racks (and yes, I run my own setup across off the shelf servers; and no, they're not nearly as redundant as a pair of IBM mainframes).
Problem is we kitted out two 42U racks in two DCs with HP and EMC kit on VMware and got four humans for five years for less than the comparable quote from IBM. And we've tested replication and failover to the same extent and didnt have to rewrite the 2 million lines or so of code we have...
> All of which are accounted for by having two or more of these, combined with the feature they call (I'm not kidding) Geographically Dispersed Parallel Sysplex (GDPS).
And it is an awesome thing - although I didn't realise it supported zVM these days, rather than just zOS.
In any case, you've still got two baskets, which was my point.
You can hook up multiple IBM mainframes remotely and set them up to automatically ensure consistent replication of machine state to various extents depending on your reliability vs. performance tradeoffs and replication distance (latency being the issue), all the way up to active-active operation across systems.
So in other words: It works far better than the failover options most people deploy on their off the shelf servers in their self-wired racks (and yes, I run my own setup across off the shelf servers; and no, they're not nearly as redundant as a pair of IBM mainframes).