Re: [libvirt] [PATCH] bridge: Add --dhcp-no-override option to dnsmasq

As confirmed on irc, the oldest distros we care about are RHEL-5 and Debian stable and both have dnsmasq-2.45. Requiring 2.41 is fine then. Given the conditional ACK from Eric, I'm going to push the following patch soon: bridge: Add --dhcp-no-override option to dnsmasq --dhcp-no-override description from dnsmasq man page: Disable re-use of the DHCP servername and filename fields as extra option space. If it can, dnsmasq moves the boot server and filename information (from dhcp-boot) out of their dedicated fields into DHCP options. This make extra space available in the DHCP packet for options but can, rarely, confuse old or broken clients. This flag forces "simple and safe" behaviour to avoid problems in such a case. It seems some virtual network card ROMs are this old/buggy so let's add --dhcp-no-override as a workaround for them. We don't use extra DHCP options so this should be safe. The option was added in dnsmasq-2.41, which becomes the minimum required version. --- libvirt.spec.in | 4 ++-- src/network/bridge_driver.c | 3 +++ 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/libvirt.spec.in b/libvirt.spec.in index c666a70..cc3e8e2 100644 --- a/libvirt.spec.in +++ b/libvirt.spec.in @@ -200,7 +200,7 @@ Requires: %{name}-client = %{version}-%{release} Requires: bridge-utils %endif %if %{with_network} -Requires: dnsmasq +Requires: dnsmasq >= 2.41 Requires: iptables %endif %if %{with_nwfilter} @@ -298,7 +298,7 @@ BuildRequires: avahi-devel BuildRequires: libselinux-devel %endif %if %{with_network} -BuildRequires: dnsmasq +BuildRequires: dnsmasq >= 2.41 %endif BuildRequires: bridge-utils %if %{with_sasl} diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c index f247a0f..d6d3068 100644 --- a/src/network/bridge_driver.c +++ b/src/network/bridge_driver.c @@ -427,6 +427,8 @@ networkBuildDnsmasqArgv(virNetworkObjPtr network, (2 * network->def->nranges) + /* --dhcp-range 10.0.0.2,10.0.0.254 */ /* --dhcp-lease-max=xxx if needed */ (network->def->nranges ? 1 : 0) + + /* --dhcp-no-override if needed */ + (network->def->nranges ? 1 : 0) + /* --dhcp-hostsfile=/var/lib/dnsmasq/$NAME.hostsfile */ (network->def->nhosts > 0 ? 1 : 0) + /* --enable-tftp --tftp-root /srv/tftp */ @@ -497,6 +499,7 @@ networkBuildDnsmasqArgv(virNetworkObjPtr network, if (network->def->nranges > 0) { snprintf(buf, sizeof(buf), "--dhcp-lease-max=%d", nbleases); APPEND_ARG(*argv, i++, buf); + APPEND_ARG(*argv, i++, "--dhcp-no-override"); } if (network->def->nhosts > 0) { -- 1.7.2