16 Jun, 2009, Cratylus wrote in the 41st comment:
Votes: 0
quixadhal said:
Out of curiosity, how common is it to have this kind of chroot jail instead of just installing your own linux in a full VM? I've never looked at hosting, but whenever we talked about it at work it was either putting your own hardware in someone's rack, or getting a VM that you could install/backup remotely, and it acted like a full machine with a wimpy CPU.

Just to clarify, openvz is not *quite* a chroot jail…it has some fancy features giving
it control and isolation that has advantages over the classic chroot jail…and I'm
pretty sure openvz devs bristle at the comparison :)

I called it that because from my perspective it's practically the same thing,
given that there's just one kernel in play for multiple instances.

OpenVZ is actually very common because it's pretty cheap, resource-wise and
service-wise. It's typically the "low service tier" on vpses for the very reason that
people tend to bump up against limitations more often than on other types
of virtualization. The performance can also be pretty lame…not because of some
fault of OpenVZ, but because the way memory is presented, you could easily
be working mostly in the host OS's swap and not even know it…and this is probably
pretty common when a bunch of vm's are sardined onto a host OS.

Xen is also pretty common, but pricier since hosts have to know what they're doing
a little more than with OpenVZ, and it's harder for them to play resource games
(like pretending to give you more ram than they actually do). It's not at all a chroot
jail…you have your own kernel and stuff.

Both types of vm's act like you'd expect a vm to act for the most part. You can
shut them down, install packages, etc…very much like a vmware guest. Except,
of course, that OpenVZ kinda sucks in the way already described :)

17 Jun, 2009, Banner wrote in the 42nd comment:
Votes: 0
Cratylus said:
If there's no error, just a blank page, and it happens when
trying to access php stuff after a migration, the chances are that
you've got a config file in your php app pointing to the wrong spot.


I found the problem. Installing the mpm_worker_thread for Apache2 uninstalled phpmyadmin and a few critical mysql components, so I simply needed to reinstall them, restart mysql and Apache2 and then it fired right up.

EDIT: And for the record, the solution to my core dumping problem was to get a Xen-based server with Linode. Core dumps worked with a fresh install, no configuration needed. Quantact did have amazing support though, but unfortunately the Linode control panel is amazing compared to Quantact's, and they also offer more bang for the buck.