On Sat, 19 Sep 2009, Luke S Crawford wrote: > Lamont Granquist <[email protected]> writes: > >>> one thing that a lot of people initially see is 'hey, we are reducing the >>> number of servers that we run, so we will also save a huge amount of >>> sysadmin >>> time', what they don't recognize is that you have the same number of systems >>> to patch (plus the new host systems that you didn't have before), so unless >>> you implement management software at the same time your time requriements go >>> up, not down. >> >> yeah, well since i've got a strong configuration management background >> that is one thing that is obviously wrong. > > Many people outside the field think that most SysAdmin time is spent monkeying > with hardware. But there is some truth to the 'virtualization can save > you sysadmin time' marketing bulletpoint, assuming you have a big > 'maybe' or 'sometimes' in there. > > If you really do need a whole lot of trivially sized services, virtualization > and giving each small service it's own 'server' can sometimes be less work > than making your mailserver config play nice with the apache config and the > fileserver config and the db config on the one giant monster server. > In that case, virtualization can also make it easier to make the db > server the problem of bob in accounting without letting him have root on > your webserver, and let the fileserver be the problem of jane in IT without > letting her have root on the developers' git server. Granted, you can do > the same thing by just running different services under different users, but > that's easier with some applications than with others.
if that is your problem, just create chroot sandboxes with your different services in them. that let's you get most of the isolation of VMs, but with non of the CPU/ram overhead. this is just slightly more sysadmin work than virtual servers, but significantly less than getting everything to work in one system image. among other things this lets you have different 'installs' with different library versions, even different distros (basicly as long as they don't require incompatible kernel versions or different versions of a service listening on the same port of localhost) >> i spent quite a bit of time beating up some citrix reps drilling down into >> what they can do for box builds and configuration management, and >> virtualization's approach was basically to increase the velocity of being >> able to do the disk duping approach to deployment and configuration >> management which does nothing for life-cycle configuration management >> (e.g. changing /etc/resolv.conf on every existing deployed server). i've >> seen virtualization pitched in CTO/CEO-focused materials as "solving" >> configuration management, however. > > How come anyone still listens to sales? I mean, the last person I > am going to take advice from is someone who has an obvious interest > in deceiving me. as far as management goes, the rational is that they are the experts who know more than their staff does (on this particular topic anyway) David Lang _______________________________________________ Tech mailing list [email protected] http://lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
