On Mon, Aug 07, 2017 at 10:27:26AM -0700, Guru Shetty wrote: > On 7 August 2017 at 10:14, Ben Pfaff <[email protected]> wrote: > > > On Mon, Aug 07, 2017 at 10:10:40AM -0700, Guru Shetty wrote: > > > On 7 August 2017 at 09:50, Ben Pfaff <[email protected]> wrote: > > > > > > > On Sun, Aug 06, 2017 at 10:56:30PM -0700, Gurucharan Shetty wrote: > > > > > We had one note about the issues with adding OVS interfaces > > > > > in the "auto" section. This commit adds another note about > > > > > how adding OVS bridges in the "auto" section can cause > > > > > race conditions with systemd. > > > > > > > > > > Signed-off-by: Gurucharan Shetty <[email protected]> > > > > > --- > > > > > debian/openvswitch-switch.README.Debian | 8 ++++++++ > > > > > 1 file changed, 8 insertions(+) > > > > > > > > > > diff --git a/debian/openvswitch-switch.README.Debian > > > > b/debian/openvswitch-switch.README.Debian > > > > > index 5f8f823..d236824 100644 > > > > > --- a/debian/openvswitch-switch.README.Debian > > > > > +++ b/debian/openvswitch-switch.README.Debian > > > > > @@ -231,3 +231,11 @@ in the 'auto' section, openvswitch-switch will > > > > forcefully be started when > > > > > ifupdown kicks in. In a case like this, the admin needs to make sure > > > > that /usr > > > > > has already been mounted and that a remote $syslog (if used) is > > ready to > > > > > receive openvswitch logs. > > > > > + > > > > > +* With systemd, adding openvswitch bridges in the 'auto' section of > > the > > > > > +'interfaces' file can cause race conditions. Debian systems have > > added > > > > a > > > > > +systemd [email protected] file. This file will call ifdown and ifup on > > > > interfaces > > > > > +in "auto" section automatically when they disappear and appear > > > > respectively. > > > > > +This will cause race conditions if you delete and add the same > > bridges > > > > using > > > > > +tools like "ovs-vsctl" or "ovs-dpctl". This is also a problem when > > you > > > > > +upgrade your openvswitch kernel module using commands like > > > > 'force-reload-kmod'. > > > > > > > > I'm not really sure what the "auto" section is. Do you just mean that > > > > they should not add lines like "auto br0" where br0 is an Open vSwitch > > > > bridge? (I do see that there is already some wording about an "auto" > > > > section.) > > > > > > > Yes. Adding lines like "auto br0" is a license for systemd to handle them > > > "automatically". > > > > OK, can we reword this (including the existing text) a little bit, to be > > more precise? I think that referring to this feature as a section is > > going to cause confusion for others, too. > > > > How about the following diff to the existing text (and then repeat the same > in this commit)?: > > diff --git a/debian/openvswitch-switch.README.Debian > b/debian/openvswitch-switch.README. > index 5f8f823..200266e 100644 > --- a/debian/openvswitch-switch.README.Debian > +++ b/debian/openvswitch-switch.README.Debian > @@ -223,7 +223,8 @@ script that depends on openvswitch but starts before > it, needs to be > to depend on openvswitch-switch too. > > * Ideally, an admin should not add openvswitch bridges in the 'auto' > -section of the 'interfaces' file. This is because, when ifupdown starts > +section of the 'interfaces' file (i.e., if "br0" is a OVS bridge, you > should > +not have a line "auto br0"). This is because, when ifupdown starts > working on bridges listed in 'auto', openvswitch has not yet started. > > But, if the admin wants to go down this route and adds openvswitch bridges
Acked-by: Ben Pfaff <[email protected]> _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
