Daniel P. Berrange
2007-Jul-23 03:26 UTC
[Xen-devel] How to stop XenD creating bridge devices on startup?
Prior to starting XenD I have a single bridge device ''eth0''
containing a
physical interface ''peth0'':
# brctl show
bridge name bridge id STP enabled interfaces
eth0 8000.00161745105a no peth0
The /etc/xen/xend-config.sxp is configured to a no-op network-script config,
and yet when I start XenD:
# /etc/init.d/xend start
Starting xend: [ OK ]
It still feels the need to create a whole bunch of bridge devices...
# brctl show
bridge name bridge id STP enabled interfaces
eth0 8000.00161745105a no peth0
virbr0 8000.000000000000 no
virbr1 8000.000000000000 no
vnet0 8000.000000000000 no
These bridge devices it is creating correspond to bridge devices I had
previously configured on the host, but since deleted. XenD happily
re-creates them every time it starts.
This problem is pretty repeatable, if you simply define a bridge and
then start & stop Xen
# brctl addbr foo
# /etc/init.d/xend start
Starting xend: [ OK ]
# /etc/init.d/xend stop
Stopping xend: [ OK ]
Now delete the bridge and start Xend again
# brctl delbr foo
# /etc/init.d/xend start
Starting xend: [ OK ]
Low and behold it has re-created the bridge
# brctl show | grep foo
foo 8000.000000000000 no
This is seriously unhelpful behaviour, the only way to kill it seems to be
to stop XenD and then hand edit its persistent state file.
The problem code is in XendNode.py
bridges = Brctl.get_state().keys()
configured_bridges = [XendAPIStore.get(
network_uuid, "network")
.get_name_label()
for network_uuid in XendNetwork.get_all()]
unconfigured_bridges = [bridge
for bridge in bridges
if bridge not in configured_bridges]
for unconfigured_bridge in unconfigured_bridges:
XendNetwork.create_phy(unconfigured_bridge)
This re-creates asks brctl for a list of all devices, records all their
names and then re-creates any it previously saw, but which no longer
exist. In essence once XenD has seen a bridge you can never remove it.
IMHO, any devices XenD sees from ''brctl'' need to be marked as
''transient''
in some way and not kept in XenD persistent state file - it should only
be re-creating bridges that the user created via XenD''s APIs
Dan.
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Luiz Vitor Martinez Cardoso
2007-Jul-25 15:07 UTC
Re: [Xen-devel] How to stop XenD creating bridge devices on startup?
Hi, Bridge creating is enabled in xen-config.sxp Comment this lines #(network-script ''network-bridge netdev=eth1'') #(network-script network-bridge) And uncomment this line: (network-script network-dummy) Regards, Luiz Vitor Martinez Cardoso (Grabber) Em Mon, 23 Jul 2007 04:26:37 +0100 "Daniel P. Berrange" <berrange@redhat.com> escreveu:> Prior to starting XenD I have a single bridge device ''eth0'' containing a > physical interface ''peth0'': > > # brctl show > bridge name bridge id STP enabled interfaces > eth0 8000.00161745105a no peth0 > > The /etc/xen/xend-config.sxp is configured to a no-op network-script config, > and yet when I start XenD: > > # /etc/init.d/xend start > Starting xend: [ OK ] > > It still feels the need to create a whole bunch of bridge devices... > > # brctl show > bridge name bridge id STP enabled interfaces > eth0 8000.00161745105a no peth0 > virbr0 8000.000000000000 no > virbr1 8000.000000000000 no > vnet0 8000.000000000000 no > > These bridge devices it is creating correspond to bridge devices I had > previously configured on the host, but since deleted. XenD happily > re-creates them every time it starts. > > This problem is pretty repeatable, if you simply define a bridge and > then start & stop Xen > > # brctl addbr foo > # /etc/init.d/xend start > Starting xend: [ OK ] > # /etc/init.d/xend stop > Stopping xend: [ OK ] > > Now delete the bridge and start Xend again > > # brctl delbr foo > # /etc/init.d/xend start > Starting xend: [ OK ] > > Low and behold it has re-created the bridge > > # brctl show | grep foo > foo 8000.000000000000 no > > This is seriously unhelpful behaviour, the only way to kill it seems to be > to stop XenD and then hand edit its persistent state file. > > The problem code is in XendNode.py > > bridges = Brctl.get_state().keys() > configured_bridges = [XendAPIStore.get( > network_uuid, "network") > .get_name_label() > for network_uuid in XendNetwork.get_all()] > unconfigured_bridges = [bridge > for bridge in bridges > if bridge not in configured_bridges] > for unconfigured_bridge in unconfigured_bridges: > XendNetwork.create_phy(unconfigured_bridge) > > This re-creates asks brctl for a list of all devices, records all their > names and then re-creates any it previously saw, but which no longer > exist. In essence once XenD has seen a bridge you can never remove it. > IMHO, any devices XenD sees from ''brctl'' need to be marked as ''transient'' > in some way and not kept in XenD persistent state file - it should only > be re-creating bridges that the user created via XenD''s APIs > > Dan._______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel