John Alberts wrote: > Thanks. That clears things up quite a bit for the most part. > One thing about setting up a new guest os though. > The process would be to just create a new guest with a tarball or > whatever. This would create a typical guest os that would consume the > typical amount of disk space that I would expect. Then create the > /etc/vservers/$GUEST/apps/vunify directory. Then I start the guest os > and some magic unification stuff will happen. This will reduce the > overall disk footprint of the new running guest. > From that point, I can use and/or customize the scripts you supplied to > help manage the upgrade process. > > Obviously, the part that I'm still not clear about is what happens > during the part that I said "some magic unification stuff will happen". ;) Sorry I skipped that part. After you have your guest created/configured/running you need to run the command: vserver $GUEST hashify The only time you'll see a saving in disk space is if you have two or more guests unified/hashified. Plus if I understand the process correctly you will get a better utilization of memory also. I understand the principal but can't articulate it without sounding the fool. I believe the closest would be the setting the sticky bit on an executable. Here is a link (which you may already have found) that explains it better than I can. http://linux-vserver.org/Frequently_Asked_Questions#Unification > Also, I have some RHEL5 guests on a RHEL5 hosts, but I also have quite a > few Gentoo guests on a Gentoo host. I think I remember reading or > hearing somewhere that unification doesn't work at all for Gentoo. Can > someone confirm this? After re-reading it I think vhashify (verses vunify) should work with gentoo. Rod -- > Thanks again for your input. > John > > > > On Tue, Aug 26, 2008 at 12:05 PM, Roderick A. Anderson <raanders@acm.org > <mailto:raanders@acm.org>> wrote: > > John Alberts wrote: > > Unification was just brought up on another recent thread and I > have some questions about it that google doesn't seem to be > finding the answers for me. > > Is there any good documentation for using unification? The > linux-vserver site mentions it briefly in the FAQ section, but > that's all I could really find. > > > John I think I can help with a couple of these. > > > Specifically, I'm looking for: > 1. What I would do to initially implement unification on a host > with multiple guests currently running? > > > mkdir /etc/vservers/$GUEST/apps/vunify > > > 2. Is there anything special when creating a new guest that I > would like to use unification? > > > mkdir /etc/vservers/$GUEST/apps/vunify > > > 3. What is the process for upgrading the guests? Can they > somehow be upgraded on one guest os and have the other guests > link to those new files? > > > I don't think. > > I use these scripts: > > vhashify.sh > #!/bin/bash > > echo Beginning guest unification > > for g in \ > $(find /etc/vservers/*/* -name vunify | sort | cut -d '/' -f 4 ) ; \ > do \ > echo -e "\tHashifying $g" ; \ > vserver $g hashify ; \ > done > > echo Begin cleanup > > find /vservers/.hash -type f -links 1 -print0 | xargs -0 /bin/rm > > echo guest unification Complete > > Before I run the above script I run the following one. I do use > CentOS so it uses yum/vyum. If you're using a different > distribution or multiple distributions with different package > management methods you'll have to pound this into a different shape. > > vupdate.sh > #!/bin/bash > > updateGuest() { > > if [ -e /etc/vservers/$g/apps/pkgmgmt/internal ]; then > echo using internal yum > vserver $g exec yum -y update > else > echo using external vyum > vyum $g -- -y update > fi > > } > > echo Beginning guests update > > for g in \ > $(find /etc/vservers/*/* -name vunify | sort | cut -d '/' -f 4 ) ; \ > do \ > echo -en "\tUpdating $g" ; \ > updateGuest ; \ > done > > echo guest updates Complete > > There is a vupdateworld script but I've never taken the time to see > if it does what I want it to. Mine looks to see if package > management is internalized. > > > 4. Are there any gotchas to look out for when using > unification? Special things that need to be done when adding or > removing applications or files from a single guest os that is > using unification for instance? > > > My understanding is if you're not using a RPM based distribution you > may have to do a bit more preparation so the unification doesn't > unify files it shouldn't. > > > Good Computing, > Rod > -- > > > Thanks > John Alberts > > > -- > John Alberts > > > > > > -- > John Alberts >