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Technology Stocks : Network Appliance -- Ignore unavailable to you. Want to Upgrade?

To: FiloF who wrote (5832)	1/17/2001 10:04:01 PM
From: DownSouth	Read Replies (2) \| Respond to of 10934

EMC's IP4700 is already cheaper and superior to NTAP's filers because it achieves HA (high availability) in one box while you have to cluster two NTAP filers to achieve high availability. I believe that the IP4700's SPEC SFS benchmarks have shown that it is not superior in price/performance, so I dispute the "cheaper" statement. Turn on RAID in the IP4700, and the performance would be dismal, compared to NTAP. Single filer, non clustered configurations are achieving field measured availability in excess of 99.995%, including down time for software upgrades. Clustered configs of two filers are adding a few .001% to that. A single filer has lots of redundancy built in, so this statement deserves a lot more examination than what we see here. (NTAP has hot spare drives, redundant power supplies. The INTC CPU and RAM is not redundant, but my experience is that INTC CPUs and RAM don't fail.) The IP4700 uses EMC's Snapview technology which provides up to 92 read-only snapshots compared to NTAP's Snapshot technology which provides up to 31 read-only snapshots. Well, EMC's Snapview technology is not as efficient as NTAP's SNAPSHOT. NTAP's snapshots have no storage overhead, except as individual 4K blocks are updated after the SNAPSHOT is taken. NTAP supports 20 SNAPSHOTS per RAID volume, so the limit of 31 is a mystery to me. I have heard of no complaints about the 20 SNAPSHOT limit. A customer can set up a SNAPSHOT plan that provides for daily SNAPSHOTs that rollover every n-days, weekly SNAPSHOTs that rollover every n weeks, and, perhaps, hourly SNAPSHOTs that roller over every n-hours. You just have to be sure that n+n+n does not exceed 20 on any volume. Remember, SNAPSHOTS are used so that users can retrieve old version of individual files, consistent backups can be run without interrupting production, and consistent reports can be run without interrupting production. A multi-terabyte filer will have several RAID volumes for the sake of minimizing the probability of a two-disk failure in a single RAID array and to simplify the backup and SNAPSHOT processes, which are done a volume at a time. One of EMC's weaknesses is the storage overhead of its Snapview technology. It really drives down Price/performance. Celerra plugs off a Symmetrix which utilitizes TimeFinder technology which provides up to 8 read and write full copies. I don't think anyone will seriously compare NTAP's asychronous mirroring technology with EMC's SRDF which provides synchronous and asynchronous mirroring over at least 8 network protocols. NTAP does not use an "asynchronous mirroring". NTAP uses RAID 4, which is not mirroring--in any sense. Mirroring is a very high overhead method in terms of storage and I/O overhead. NTAP supports every standard network protocol and filers can have multiple network interface cards, each supporting multiple network interfaces. This statement is very confusing to me, so I don't understand what the writer is trying to say. One of the most profound advantages that EMC has over NTAP, and the rest of the industry for that matter, is that it invested early in a proprietary quality assurance process that insures that its products are the most reliable. Not only does EMC maintain close engineering links with their key suppliers , but they subject components and the final system configurations to rigorous stress testing that takes at least 3 weeks. Nothing profound here. NTAP also maintains close relationships with its component suppliers, to the point of controlling disk drive microcode releases. NTAP does a final burn in of customer ordered configs. I doubt its 3 weeks, though. That's just not necessary. WRT to "proprietary quality assurance", I guess NTAP's QA is proprietary too, but so what? Nobody else comes close. NTAP, for example, has a business model that generally depends on increasing the turnover rate from the current 11x. EMC is already very profitable at 4x because 80% of revenues come from customers who appreciate the quality of its products...> I don't know what this 4x and 11x stuff is. And the fact that EMC gets 80% of its revenues from existing customers is nothing to brag about. That means they are not penetrating new accounts at the rate of NTAP. Perhaps the writer is trying to learn. He/she obviously has some room to do so.

To: FiloF who wrote (5832)	1/17/2001 10:41:51 PM
From: DownSouth	Read Replies (1) \| Respond to of 10934

FiloF, I just hit the URL to Gus's post and need to expand on my response, now that I see the full context of what Gus was saying. (I have lots of respect for Gus's expertise on EMC, though I don't think he really "gets" what NTAP is doing.) Network Appliance is still unable to provide syncrhronous mirroring and its asynchronous mirroring technology is remarkably primitive in comparision to EMC's SRDF. This statement is correct. However, the DAFS/VI products and some software development due this year will solve this for NTAP. They will be able to mirror filers over long distances in a much more efficient manner than does EMC, mostly because of SNAPSHOTs inherent advantages. The rest of Gus's post is a bit, well, uncompelling. His slam of Gigabit E-net as the NTAP disrupting technology is out of the blue. I have heard no one claim that GbE is the disruptive element of NTAP. DAFS/VI, however, may just be so. I honestly don't have the interest to respond to any details of Gus's post.