[Date Prev][Date Next] [Chronological] [Thread] [Top]

Re: VMware and mirror/multimaster

Howard Chu wrote:
Dave Horsfall wrote: 
Has anyone tried mirroring or multimaster under VMware i.e. are the
virtual clocks stable enough?  We're starting to use VMware to cut down on
the number of physical hosts, but I'd like to use the latest 2.4 features
as well.

I don't have any long-term experience with that setup, just use VMware for
short-duration tests. My suspicion is that the clock stability isn't very
good, and ntpd can't correct for it...

Thinking about this some more - why would you ever do this? If you're consolidating many physical servers into a single physical server, just run a single slapd on the consolidated server. You'll have more RAM available and much less overhead.

The only good reason to run multiple masters is when you actually have multiple physical servers, and they're set up such that they won't typically all fail at once (e.g., in geographically remote locations so that a disaster in one location doesn't affect the others). If all of your servers are going to just be in VMs running on the same machine, and they're all replicating with each other, you have no hardware redundancy, so you may as well just run a single slapd on the real machine.

--
  -- Howard Chu
  CTO, Symas Corp.           http://www.symas.com
  Director, Highland Sun     http://highlandsun.com/hyc/
  Chief Architect, OpenLDAP  http://www.openldap.org/project/