1 .TH ovs\-vlan\-test 1 "December 2010" "Open vSwitch" "Open vSwitch Manual"
4 \fBovs\-vlan\-test\fR \- check Linux drivers for problems with vlan traffic
7 \fBovs\-vlan\-test\fR [\fB\-s\fR | \fB\-\-server\fR] \fIcontrol_ip\fR \fIvlan_ip\fR
11 The \fBovs\-vlan\-test\fR program may be used to check for problems sending
12 802.1Q traffic which may occur when running Open vSwitch. These problems can
13 occur when Open vSwitch is used to send 802.1Q traffic through physical
14 interfaces running certain drivers of certain Linux kernel versions. To run a
15 test, configure Open vSwitch to tag traffic originating from \fIvlan_ip\fR and
16 forward it out the target interface. Then run the \fBovs\-vlan\-test\fR in
17 client mode connecting to an \fBovs\-vlan\-test\fR server.
18 \fBovs\-vlan\-test\fR will display "OK" if it did not detect problems.
20 Some examples of the types of problems that may be encountered are:
22 When NICs use vlan stripping on receive they must pass a pointer to
23 a vlan group when reporting the stripped tag to the networking core.
24 If there is no vlan group in use then some drivers just drop the
25 extracted tag. Drivers are supposed to only enable stripping if a
26 vlan group is registered but not all of them do that.
29 Some drivers size their receive buffers based on whether a vlan
30 group is enabled, meaning that a maximum size packet with a vlan tag
31 will not fit if a vlan group is not configured.
34 On transmit some drivers expect that vlan acceleration will be used
35 if it is available (which can only be done if a vlan group is
36 configured). In these cases, the driver may fail to parse the packet
37 and correctly setup checksum offloading and/or TSO.
40 An \fBovs\-vlan\-test\fR client may be run on a host to check for VLAN
41 connectivity problems. The client must be able to establish HTTP connections
42 with an \fBovs\-vlan\-test\fR server located at the specified \fIcontrol_ip\fR
43 address. UDP traffic sourced at \fIvlan_ip\fR should be tagged and directed out
44 the interface whose connectivity is being tested.
47 To conduct tests, an \fBovs\-vlan\-test\fR server must be running on a host
48 known not to have VLAN connectivity problems. The server must have a
49 \fIcontrol_ip\fR on a non\-VLAN network which clients can establish
50 connectivity with. It must also have a \fIvlan_ip\fR address on a VLAN network
51 which clients will use to test their VLAN connectivity. Multiple clients may
52 test against a single \fBovs\-vlan\-test\fR server concurrently.
57 \fB\-s\fR, \fB\-\-server\fR
62 Display the Linux kernel version and driver of \fBeth1\fR.
69 Set up a bridge which forwards traffic originating from \fB1.2.3.4\fR out
70 \fBeth1\fR with VLAN tag 10.
72 .B ovs\-vsctl \-\- add\-br vlan\-br \(rs
74 .B \-\- add\-port vlan\-br eth1 \(rs
76 .B \-\- add\-port vlan\-br vlan\-br\-tag tag=10 \(rs
78 .B \-\- set Interface vlan\-br\-tag type=internal
80 .B ifconfig vlan\-br\-tag up 5.6.7.8
83 Run an \fBovs\-vlan\-test\fR server listening for client control traffic on
84 5.6.7.8 port 80 and VLAN traffic on the default port of 1.2.3.0.
86 .B ovs\-vlan\-test \-s 5.6.7.8:80 1.2.3.0
89 Run an \fBovs\-vlan\-test\fR client with a control server located at 5.6.7.8
90 port 80 and a local VLAN ip of 1.2.3.4.
92 .B ovs\-vlan\-test 5.6.7.8:80 1.2.3.4
98 .BR ovs\-vswitchd (8),