[libvirt] [RFC/PATCH 1/2] network: add dnsmasq option 'dhcp-authoritative'

The dnsmasq man page recommends that dhcp-authoritative "should be set when dnsmasq is definitely the only DHCP server on a network". This is the case for libvirt-managed virtual networks. The effect of this is that VMs that fail to renew their DHCP lease in time (e.g. if the VM or host is suspended) will be able to re-acquire the lease even if it's expired, unless the IP address has been taken by some other host. This avoids various annoyances caused by changing VM IP addresses. --- src/network/bridge_driver.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c index 7b99aca..cb4fb1c 100644 --- a/src/network/bridge_driver.c +++ b/src/network/bridge_driver.c @@ -1258,8 +1258,10 @@ networkDnsmasqConfContents(virNetworkObjPtr network, /* Note: the following is IPv4 only */ if (VIR_SOCKET_ADDR_IS_FAMILY(&ipdef->address, AF_INET)) { - if (ipdef->nranges || ipdef->nhosts) + if (ipdef->nranges || ipdef->nhosts) { virBufferAddLit(&configbuf, "dhcp-no-override\n"); + virBufferAddLit(&configbuf, "dhcp-authoritative\n"); + } if (ipdef->tftproot) { virBufferAddLit(&configbuf, "enable-tftp\n"); -- 2.9.3