On Tuesday 13 July 2010 16:28:50 Doug Simmons wrote: > > Do any of the list members have any experience with this service?
We are pondering a different cloud system based on XEN offering similar on a smaller scale than Amazon. Pricing is slightly cheaper, but not much in it. They charge for disk I/O bandwidth which required some quick checks on what we do, perils of expensive external storage systems. In our case we've done a little more than 20 minutes research, but the conclusions aren't clear cut. I think the motivation for moving to a cloud system is probably not solely financial, one has to expect that the option to migrate instances will add robustness, the option to add systems flexibility, and the scalability are the factors one is looking for. Also these systems have large robust storage systems which are beyond the pockets of most businesses. My concern still is availability. Amazon EC2 I hear good things about. A couple of other providers we looked at are not bad, most don't have a track record you could point at and think "that is better than a decent hosting provider" and dedicated hardware - we routinely get 1 year plus uptimes on DELL hardware boxes that are a decade old - when we see top cloud providers off air for a couple of days at a time it doesn't convince me. I've yet to use a virtualization product that didn't have virtualization "bugs", i.e. errors, downtime, or problems due to the virtualization process. The OpenVZ stuff we tried didn't memory map files correctly, one provider using XEN migrated our instance to different hardware for maintenance and when it woke up milliseconds later it was 1914 (Postfix said it wasn't doing anything till the date was plausible - which was probably wise - but did nothing for availability). What I've read of EC2 is that it is rather idiosyncratic compared to more recent virtualization offerings elsewhere, on the other hand they seem to have been free of major problems for a while. The XEN provider we've looked at most closely seem promising, they seem to have resolved a lot of issues with their earlier system, but I have concerns at scalability because they limit the available RAM to each instance somewhat and when you have hundreds of gigabytes of data it would be nice to know you could scale RAM to something more substantial if needed, and serious disk space is expensive in these storage arrays. And they have zero track record on their new system because it is new. On the other hand I'm not THAT scared of virtualization just want to test it the whole way, which is time consuming. One provider looked solid, but the pricing was high, and the marketing/emphasis was all to hosting enterprise servers rather than web servers (which is what we want). Anyone gone with a dual provider strategy - where they create instances at different cloud providers, and fail across on long outages? As that would address my key concerns about reliability, but it looks expensive and complex to implement. If there were relatively cheap network storage systems around with suitable characteristics I'd be tempted to build our own XEN hosting system to get the advantages of virtualisation without the pain of a third party relationship. But I haven't read that bit of 'the Book of XEN' yet, and suspect the answer is "no". _______________________________________________ Linux-PowerEdge mailing list [email protected] https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
