diff --git a/doc/config-reference/networking/section_networking-plugins-ml2.xml b/doc/config-reference/networking/section_networking-plugins-ml2.xml index fae17f6eed..add49ba6ba 100644 --- a/doc/config-reference/networking/section_networking-plugins-ml2.xml +++ b/doc/config-reference/networking/section_networking-plugins-ml2.xml @@ -10,33 +10,28 @@ components separately. This section describes these configuration options. - MTU bug with VXLAN tunnelling - Due to a bug in Linux Bridge software maximum - transmission unit (MTU) handling, using VXLAN tunnels does - not work by default. + Configure MTU for VXLAN tunnelling + Specific MTU configuration is necessary for VXLAN to function + as expected: - A simple workaround is to increase the MTU value - of the physical interface and physical switch - fabric by at least 50 bytes. For example, increase - the MTU value to 1550. This value enables an - automatic 50-byte MTU difference between the - physical interface (1500) and the VXLAN interface - (automatically 1500-50 = 1450). An MTU value of - 1450 causes issues when virtual machine taps are - configured at an MTU value of 1500. + One option is to increase the MTU value of the physical + interface and physical switch fabric by at least 50 bytes. + For example, increase the MTU value to 1550. This value + enables an automatic 50-byte MTU difference between the + physical interface (1500) and the VXLAN interface + (automatically 1500-50 = 1450). An MTU value of 1450 causes + issues when virtual machine taps are configured at an MTU + value of 1500. - Another workaround is to decrease the virtual - Ethernet devices' MTU. Set the - option to - 1450 in the neutron.conf - file, and set all guest virtual machines' MTU to - the same value by using a DHCP option. For - information about how to use this option, see - Configure OVS plug-in. + Another option is to decrease the virtual ethernet + devices' MTU. Set the + option to 1450 in the neutron.conf file, + and set all guest virtual machines' MTU to the same value by + using a DHCP option. For information about how to use this + option, see + Configure OVS plug-in.