Re: [libvirt] [PATCHv2 0/7] interface: new public API for networkconfig change transactions
On 05/19/2011 06:14 PM, Christian Benvenuti (benve) wrote:
I have one generic question.
I know it is not a new problem, and it is not necessarily something
worth investing time and code on, but what if the admin
(directly or indirectly by activating some features)
changes the interface configuration in between a BEGIN and
a ROLLBACK with commands that do not go through virsh/libvirtd?
Would ROLLBACK rollback those changes too?
Yes, it would. This is only because of the particular implementation in
the netcf library, though. ncf_change_begin() saves off a copy of all
the network config files to a "snapshot" directory; ncf_change_commit()
deletes that snapshot, and ncf_change_rollback() copies back the files
that were put in the snapshot directory during ncf_change_begin().
You can see the backend of these functions (implemented as a shell
script so that it can run at boottime) at:
https://fedorahosted.org/pipermail/netcf-devel/2011-May/000562.html
Does it make sense for libvirtd to subscribe to the relevant
Netlink multicast groups to listen for such changes and flag
an interface as "tainted" in such case? This way it may
be able to generate a log or ask for a sort of extra "--force"
parameter for the ROLLBACK case.
That may be a nice thing to do, but isn't necessary for the initial
implementation.