Re: [libvirt] [PATCH] network: don't use dhcp-authoritative on static networks

"Static" DHCP networks are those where no dynamic DHCP range is defined, only a list of host entries is used to serve permanent IP addresses. On such networks, we don't want dnsmasq to reply to other requests than those statically defined. But "dhcp-authoritative" will cause dnsmasq to do just that. Therefore we can't use "dhcp-authoritative" for static networks.

Fixes: 4ac20b3ae "network: add dnsmasq option 'dhcp-authoritative'" Signed-off-by: Martin Wilck <mwilck(a)suse.com&gt; --- src/network/bridge_driver.c | 9 ++++++++- tests/networkxml2confdata/dhcp6host-routed-network.conf | 1 - 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c index ae1589d8c..17c6f3a0f 100644 --- a/src/network/bridge_driver.c +++ b/src/network/bridge_driver.c @@ -1355,7 +1355,14 @@ networkDnsmasqConfContents(virNetworkObjPtr network, if (VIR_SOCKET_ADDR_IS_FAMILY(&ipdef->address, AF_INET)) { if (ipdef->nranges || ipdef->nhosts) { virBufferAddLit(&configbuf, "dhcp-no-override\n"); - virBufferAddLit(&configbuf, "dhcp-authoritative\n"); + /* + * Use "dhcp-authoritative" only for dynamic DHCP. + * In a static-only network, it would cause dnsmasq + * to reply to requests from other hosts than those + * statically defined. + */ + if (ipdef->nranges || !ipdef->nhosts) + virBufferAddLit(&configbuf, "dhcp-authoritative\n"); } if (ipdef->tftproot) { diff --git a/tests/networkxml2confdata/dhcp6host-routed-network.conf b/tests/networkxml2confdata/dhcp6host-routed-network.conf index 87a149880..5728ee430 100644 --- a/tests/networkxml2confdata/dhcp6host-routed-network.conf +++ b/tests/networkxml2confdata/dhcp6host-routed-network.conf @@ -10,7 +10,6 @@ bind-dynamic interface=virbr1 dhcp-range=192.168.122.1,static dhcp-no-override -dhcp-authoritative dhcp-range=2001:db8:ac10:fd01::1,static,64 dhcp-hostsfile=/var/lib/libvirt/dnsmasq/local.hostsfile addn-hosts=/var/lib/libvirt/dnsmasq/local.addnhosts