Monthly Archives: May 2011

Maximum number of instances per network and race condition during VLAN creation

Last week found a race condition during VLAN creation, reported as LP#785890.
You could see it when starting lots of instances in one project after fresh reboot / new installation.

Another bug which we found is inappropriate defaults in dnsmasq which prevents having more than 150 instances per network. Reported as LP#785763.

Both bugs are fixed now and available in trunk.

Good news are that we also backported them to our Cactus build. Enjoy!


dnsmasq issue – why an instance can’t obtain DHCP lease

Many of you asked us about resolution of dnsmasq issue.
It was basically due strong default security configuration of RHEL’s iptables.
And Nova by default doesn’t create a permissive rule to allow DHCP traffic.

Resolution is simple:
iptables -I INPUT 1 -p udp --dport 67 -j ACCEPT

P.P.S. Thanks for patience. :-)