Re: [libvirt] [virt-tools-list] virt-manager destroys symlinks to guest configs
On 02/20/2012 11:21 AM, Jakub Mroziński wrote:
Hi, virt-manager after saving guest config destroy symlink to this file and creates new file. How to reproduce:
cd /etc/libvirt/qemu # mv openbsd.xml /mount/ # ln -s /mount/openbsd.xml # ls -l openbsd.xml lrwxrwxrwx 1 root root 49 Feb 20 17:09 openbsd.xml -> /mount/openbsd.xml # virt-manager
Now we need to edit host openbsd in virt-manager then "Apply" changes and we got: # ls -l openbsd.xml -rw------- 1 root root 2076 Feb 20 17:13 openbsd.xml
I have network storage and move every configuration there. On host i want have only symlinks. I know that i can do workaround, but i dont want.
This solution was working (i dont know on which version) fine but after upgrade it doesn't work.
virt-manager - 0.9.1-1 (debian testing)
virt-manager defers to libvirt for all changes like this. Did you update libvirt at the same time? - Cole
On 02/20/2012 09:58 AM, Cole Robinson wrote:
On 02/20/2012 11:21 AM, Jakub Mroziński wrote:
Hi, virt-manager after saving guest config destroy symlink to this file and creates new file. How to reproduce:
cd /etc/libvirt/qemu # mv openbsd.xml /mount/ # ln -s /mount/openbsd.xml # ls -l openbsd.xml lrwxrwxrwx 1 root root 49 Feb 20 17:09 openbsd.xml -> /mount/openbsd.xml # virt-manager
Unsupported. /etc/libvirt must be a local directory on each host, and _must not be shared_ between machines. There are a few subdirectories under /etc/libvirt and /var/lib/libvirt that can be shared (in fact, http://libvirt.org/locking.html documents that /var/lib/libvirt/sanlock must be shared to be useful), but these are the exception, not the rule.
Now we need to edit host openbsd in virt-manager then "Apply" changes and we got: # ls -l openbsd.xml -rw------- 1 root root 2076 Feb 20 17:13 openbsd.xml
Correct - libvirt will not follow symlinks when saving internal configuration, but rewrites the file from scratch without preserving the symlink. And I don't think this is a bug, since we already explicitly document that files under /etc/libvirt are internal to libvirt, and must not be shared. Rather, it is probably an intentional side-effect of a recent libvirt change to atomically update internal .xml files (libvirt used to write over internal files in a non-atomic manner, which could corrupt domains if a power outage occurred at the wrong moment).
I have network storage and move every configuration there. On host i want have only symlinks. I know that i can do workaround, but i dont want.
If you want to store your configuration in shared storage, then the only supported method of doing that is to store the XML independently of /etc/libvirt. For example, you can 'virsh dumpxml $dom > /mount/$dom.xml' to save off the configuration to shared storage, and 'virsh define /mount/$dom.xml' to reload the shared configuration if you don't trust what might be in place locally. -- Eric Blake eblake@redhat.com +1-919-301-3266 Libvirt virtualization library http://libvirt.org
participants (2)
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Cole Robinson -
Eric Blake