Normally I don't like to just plug something new. However, I am willing to make an exception for something new and different. I want to do a brief foray into the world of mainframe attach virtual tape.
We danced around this a little while back when I talked about open systems virtual tape and the market share of the respective players. Specifically, about how technology and market share in open systems virtual tape, and technology and market share in mainframe attach virtual tape are two totally different things, and it is misleading at best to say that one has any genuine relevance to the other.
In that post, I don't think I made any bones about the fact that EMC is not a market leader in the mainframe virtual tape space. I think we are honest enough to admit that the two market leaders (in terms of share and units shipped) are Sun and IBM. However, we have recently introduced a new mainframe virtual tape offering--the Disk Library for Mainframe, or DLM--and it is pretty different than anything else out there.
The big difference? There is no tape.
Both VSM and VTS (from Sun and IBM respectively) could uncharitably be described as big tape caching systems. The VTS (or TS7700 as it is called these days) has a maximum of 18 TB of disk. The VSM comes in at a whopping (ahem) 28 TB. Of course, both approaches have the undeniable benefit of being at least 10 times as expensive as you would expect to pay for equivalent capacity/capability disk. In some situations, this disk is actually 100 times as expensive as open systems virtual tape.
So what is EMC doing? Taking a different approach.
Dispensing with tape. (Not that we don't think tape has an important role to play for the mainframe, its just that we don't think it makes sense to attach it directly to the DL for Mainframe, and hide it from the OS, in a lot of cases.)
Instead we allow up to 190 TB of disk to be attached to the DLM.
That is an order of magnitude more than competitive offerings.
It is a different approach. But we have found that it offers a different and better value proposition, and a better total cost of ownership.
When you are #3 in a market with a small number of players, I think you have to be both different (objectively) and better (which is subjective). I think we have succeeded admirably on both accounts with the DLM.
But to conclude, let me bring this back to open systems virtual tape: since Sun and IBM are basically #3 (by a long shot) in the world of open systems virtual tape, I would like to know what they are doing this is either different or better?
Of course, I have been looking for an answer to that question for 3 years now. In vain.
By way of a footnote: this post is admittedly a little North American centric. So to give credit and recognition where it is due: EMC has an outstanding partnership in other geographies with Fujitsu, and in those markets, we have seen considerable success with CentricStor. CentricStor does allow you to virtualize your mainframe tape environment, and retain true physical type on the floor. It is a great product. So if that choice seems like the best approach for you, we can help with that too.