Re: [libvirt] [PATCHv2 1/7] interface: new public API for networkconfig change transactions
-----Original Message-----
From: libvir-list-bounces(a)redhat.com [mailto:libvir-list-
bounces(a)redhat.com] On Behalf Of Laine Stump
Sent: Thursday, May 19, 2011 1:51 PM
To: libvir-list(a)redhat.com
Subject: [libvirt] [PATCHv2 1/7] interface: new public API for
networkconfig change transactions
From: Michal Privoznik <mprivozn(a)redhat.com>
This is the API agreed on in:
https://www.redhat.com/archives/libvir-list/2011-May/msg00026.html
(with a slight name change to use "...begin" rather than
"...start"). This implements transactional changes to the host network
config. When a transaction is begun with ncf_change_begin(), all other
netcf APIs will continue to work as they always have, but a snapshot
of the existing config will be taken, allowing reversion (rollback,
using ncf_change_rollback()) to the exact state of config at the time
ncf_change_begin() was called. Alternately, if it's determined that
the new changes are acceptable, ncf_change_commit() can be called,
which will eliminate the snapshot and make the changes permanent.
As a failsafe measure, if neither ncf_change_commit() or
ncf_change_rollback() is called by the next time the system reboots,
the netcf-transaction initscript will be automatically called to
rollback the changes.
Why do you think the default rollback (post reboot, for non-committed
transactions) is a good default?
When/where is that automatic rollback enforced? (I could not find it in
the patches). Does it trigger a log message too?
Do you think it may make sense to have that default behavior controlled
by
a (global, ie, not per-interface) parameter?
I am not suggesting the introduction of such parameter (but I would not
be against it), but I would suggest a 4th virsh command to list at
least the interfaces with a pending (ie, not committed yet) transaction.
/Christian
---
include/libvirt/libvirt.h.in | 7 +++++++
src/libvirt_public.syms | 3 +++
2 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/include/libvirt/libvirt.h.in
b/include/libvirt/libvirt.h.in
index 7cd6e13..4a45390 100644
--- a/include/libvirt/libvirt.h.in
+++ b/include/libvirt/libvirt.h.in
@@ -1405,6 +1405,13 @@ int virInterfaceDestroy
(virInterfacePtr iface,
int virInterfaceRef (virInterfacePtr
iface);
int virInterfaceFree (virInterfacePtr
iface);
+int virInterfaceChangeBegin (virConnectPtr
conn,
+ unsigned int
flags);
+int virInterfaceChangeCommit (virConnectPtr
conn,
+ unsigned int
flags);
+int virInterfaceChangeRollback(virConnectPtr
conn,
+ unsigned int
flags);
+
/**
* virStoragePool:
*
diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms
index 0590535..f4f8262 100644
--- a/src/libvirt_public.syms
+++ b/src/libvirt_public.syms
@@ -442,6 +442,9 @@ LIBVIRT_0.9.2 {
virDomainInjectNMI;
virDomainScreenshot;
virDomainSetSchedulerParametersFlags;
+ virInterfaceChangeBegin;
+ virInterfaceChangeCommit;
+ virInterfaceChangeRollback;
} LIBVIRT_0.9.0;
# .... define new API here using predicted next version number ....
--
1.7.3.4
--
libvir-list mailing list
libvir-list(a)redhat.com
https://www.redhat.com/mailman/listinfo/libvir-list