We are already (generally) AP for most infra changes really. I'd use that model. Eventual consistency is better in this scenario.
> On Nov 8, 2013, at 6:49 PM, Chiradeep Vittal <chiradeep.vit...@citrix.com> > wrote: > > I'd also like to highlight that it isn't a trivial problem. > Let's say there's 3 regions: this means there are 3 copies of the user > database that are geographically separated by network links that fail > quite often (orders of magnitude more than intra-DC networks). > > Here we run into the consequences of the CAP theorem [1]. > We can either have a CP or AP system: either approach makes some tradeoffs: > 1. If we run a AP system, then the challenge is to resolve conflicting > updates > 2. If we run a CP system, then the challenge is to detect partitions > reliably and disallow updates during partitions. > > [1] http://en.wikipedia.org/wiki/CAP_theorem > >> On 11/7/13 11:58 AM, "Chip Childers" <chipchild...@apache.org> wrote: >> >> On Thu, Nov 7, 2013 at 2:37 PM, Chiradeep Vittal >> <chiradeep.vit...@citrix.com> wrote: >>> It may be an admin burden, but it has to be optional. There are other >>> ways >>> to achieve global sync (e.g., LDAP/AD/Oauth). >>> A lot of service providers who run cloudstack have their own user >>> database >>> / portal. In their implementations the CloudStack database is not the >>> master source of user records, but a slave. >> >> +1 to it being optional. >
