openkylin
/
libvirt
mirror of https://gitee.com/openkylin/libvirt.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

network: set mtu as a DHCP option when specified 

This adds an additional directive to the dnsmasq configuration file that
notifies clients via dhcp about the link's MTU. Guests can then choose
adjust their link accordingly.

Signed-off-by: Casey Callendrello <cdc@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
This commit is contained in:
Casey Callendrello 2018-12-11 17:05:43 +01:00 committed by Ján Tomko
parent 6dec641394
commit 682be11505
7 changed files with 93 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/network/bridge_driver.c
View File

@ -1410,6 +1410,10 @@ networkDnsmasqConfContents(virNetworkObjPtr obj,
dctx->addnhostsfile->path);
}
/* Configure DHCP to tell clients about the MTU. */
if (def->mtu > 0)
virBufferAsprintf(&configbuf, "dhcp-option=option:mtu,%d\n", def->mtu);
/* Are we doing RA instead of radvd? */
if (DNSMASQ_RA_SUPPORT(caps)) {
if (ipv6def) {

19
tests/networkxml2confdata/nat-network-mtu.conf Normal file
View File

@ -0,0 +1,19 @@
##WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE
##OVERWRITTEN AND LOST. Changes to this configuration should be made using:
## virsh net-edit default
## or other application using the libvirt API.
##
## dnsmasq conf file created by libvirt
strict-order
except-interface=lo
bind-dynamic
interface=virbr0
dhcp-range=192.168.122.2,192.168.122.254
dhcp-no-override
dhcp-authoritative
dhcp-lease-max=253
dhcp-hostsfile=/var/lib/libvirt/dnsmasq/default.hostsfile
addn-hosts=/var/lib/libvirt/dnsmasq/default.addnhosts
dhcp-option=option:mtu,7000
dhcp-range=2001:db8:ac10:fe01::1,ra-only
dhcp-range=2001:db8:ac10:fd01::1,ra-only

22
tests/networkxml2confdata/nat-network-mtu.xml Normal file
View File

@ -0,0 +1,22 @@
<network>
<name>default</name>
<uuid>81ff0d90-c91e-6742-64da-4a736edb9a9b</uuid>
<forward dev='eth1' mode='nat'/>
<bridge name='virbr0' stp='on' delay='0'/>
<mtu size='7000'/>
<ip address='192.168.122.1' netmask='255.255.255.0'>
<dhcp>
<range start='192.168.122.2' end='192.168.122.254'/>
<host mac='00:16:3e:77:e2:ed' name='a.example.com' ip='192.168.122.10'/>
<host mac='00:16:3e:3e:a9:1a' name='b.example.com' ip='192.168.122.11'/>
</dhcp>
</ip>
<ip family='ipv4' address='192.168.123.1' netmask='255.255.255.0'>
</ip>
<ip family='ipv6' address='2001:db8:ac10:fe01::1' prefix='64'>
</ip>
<ip family='ipv6' address='2001:db8:ac10:fd01::1' prefix='64'>
</ip>
<ip family='ipv4' address='10.24.10.1'>
</ip>
</network>

1
tests/networkxml2conftest.c
View File

@ -136,6 +136,7 @@ mymain(void)
DO_TEST("nat-network-dns-forwarders", full);
DO_TEST("nat-network-dns-forwarder-no-resolv", full);
DO_TEST("nat-network-dns-local-domain", full);
DO_TEST("nat-network-mtu", dhcpv6);
DO_TEST("dhcp6-network", dhcpv6);
DO_TEST("dhcp6-nat-network", dhcpv6);
DO_TEST("dhcp6host-routed-network", dhcpv6);

22
tests/networkxml2xmlin/nat-network-mtu.xml Normal file
View File

@ -0,0 +1,22 @@
<network>
<name>default</name>
<uuid>81ff0d90-c91e-6742-64da-4a736edb9a9b</uuid>
<bridge name="virbr0"/>
<mtu size='7000'/>
<forward mode="nat" dev="eth1"/>
<ip address="192.168.122.1" netmask="255.255.255.0">
<dhcp>
<range start="192.168.122.2" end="192.168.122.254"/>
<host mac="00:16:3e:77:e2:ed" name="a.example.com" ip="192.168.122.10"/>
<host mac="00:16:3e:3e:a9:1a" name="b.example.com" ip="192.168.122.11"/>
</dhcp>
</ip>
<ip family="ipv4" address="192.168.123.1" netmask="255.255.255.0">
</ip>
<ip family="ipv6" address="2001:db8:ac10:fe01::1" prefix="64">
</ip>
<ip family="ipv6" address="2001:db8:ac10:fd01::1" prefix="64">
</ip>
<ip family="ipv4" address="10.24.10.1">
</ip>
</network>

24
tests/networkxml2xmlout/nat-network-mtu.xml Normal file
View File

@ -0,0 +1,24 @@
<network>
<name>default</name>
<uuid>81ff0d90-c91e-6742-64da-4a736edb9a9b</uuid>
<forward dev='eth1' mode='nat'>
<interface dev='eth1'/>
</forward>
<bridge name='virbr0' stp='on' delay='0'/>
<mtu size='7000'/>
<ip address='192.168.122.1' netmask='255.255.255.0'>
<dhcp>
<range start='192.168.122.2' end='192.168.122.254'/>
<host mac='00:16:3e:77:e2:ed' name='a.example.com' ip='192.168.122.10'/>
<host mac='00:16:3e:3e:a9:1a' name='b.example.com' ip='192.168.122.11'/>
</dhcp>
</ip>
<ip family='ipv4' address='192.168.123.1' netmask='255.255.255.0'>
</ip>
<ip family='ipv6' address='2001:db8:ac10:fe01::1' prefix='64'>
</ip>
<ip family='ipv6' address='2001:db8:ac10:fd01::1' prefix='64'>
</ip>
<ip family='ipv4' address='10.24.10.1'>
</ip>
</network>

1
tests/networkxml2xmltest.c
View File

@ -141,6 +141,7 @@ mymain(void)
DO_TEST("nat-network-dns-forwarder-no-resolv");
DO_TEST("nat-network-forward-nat-address");
DO_TEST("nat-network-forward-nat-no-address");
DO_TEST("nat-network-mtu");
DO_TEST("8021Qbh-net");
DO_TEST("direct-net");
DO_TEST("host-bridge-net");