On Fri, Apr 11, 2014 at 05:10:08PM +0100, Brian Candler wrote: > On 11/04/2014 16:04, Gurucharan Shetty wrote: > >system-id.conf is created by the Open vSwitch startup script to store > >a UUID generated through uuidgen. During the next startups, since > >system-id.conf exists, the value inside it is used to fill > >external-ids:system-id column. > > > >You can read about it in 'man ovs-ctl' and IntegrationGuide. > This is hard to find in Ubuntu 14.04. Eventually I found the script > itself at > /usr/share/openvswitch/scripts/ovs-ctl > but the manpage is not in the package, so I got it from the git repo > in the "utilities" subdirectory.
It hadn't occurred to me that it would be useful to install the ovs-ctl manpage, because it is not usually interesting to end users, but I guess that since you're looking at it, it might be. I'll send a patch to start installing it. > According to the manpage it looks like using ovs-ctl does have the > ability to overwrite the UUID in the database with the UUID from the > file where the random UUID was stored. And digging further, > /etc/init.d/openvswitch-switch calls ovs_ctl() defined in > /usr/share/openvswitch/scripts/ovs-lib, which does call ovs-ctl. > > So I did some experiments. I modified the UUID in > /etc/openvswitch/conf.db. When I realised that it was preceded by a > header with sha1 hash, I was able to change it > > sed -i'' s/a70e2d4f/aaaaaaaa/g conf.db # a70e2d4f are the first 8 > characters of the ID in system-id.conf > > recalculate the hash, and reboot. At startup the conf.db got its > UUID reset to the one in system-id.conf (actually it appened a new > block of JSON to the conf.db) and the config was reloaded > successfully. The database isn't really meant to be edited by hand. (The right way to change the database is to use ovs-vsctl.) _______________________________________________ discuss mailing list [email protected] http://openvswitch.org/mailman/listinfo/discuss
