initial commit for Enea Linux 4.0daisy-enea

Migrated from the internal git server on the daisy-enea branch

Signed-off-by: Adrian Dudau <adrian.dudau@enea.com>

1 files changed, 96 insertions, 0 deletions

diff --git a/docs/openvswitch.txt b/docs/openvswitch.txt
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+Simple setup for connecting openvswitch to qemu/kvm
+===================================================
+This example brings up openvswitch using a private network.
+
+Preliminary notes
+=================
+1. Make sure to build kernel support for openvswitch as a module.  The
+openvswitch init scripts expect to load a module and upon success
+continue to setup the switch.  If openvswitch is compiled
+statically, the init scripts not load the ovs-vswitchd daemon
+and none of the configured bridges will show up in the interfaces
+table (ifconfig).  You can get around this limiation by running the
+following by hand:
+        # ovs-vswitchd --pidfile --detach
+
+2. Verify that ovs-vswitchd is running before proceeding:
+        # /etc/init.d/openvswitch-switch status
+        ovsdb-server is running with pid 1867
+        ovs-vswitchd is running with pid 1877
+
+3. A kernel and rootfs is required for qemu bring up.
+
+Qemu Setup
+==========
+The host requires a /etc/qemu-ifup script to setup the bridging and tap
+devices.  Qemu will invoke this qemu-ifup script at startup.  Here is
+an example script:
+$ cat /etc/qemu-fup
+        #!/bin/sh
+        # the tap is dynamically assigned and passed into this script
+        # as a parameter
+        TAP=$1
+
+        # Note: if booting over NFS, once the $ETH0 device is added to the bridge,
+        # your host will be unusable.  In that case, setup networking
+        # init scripts appropriately and change the following to work
+        # with it.
+        ETH0="eth1"
+        NETMASK=255.255.255.0
+        IP=192.168.1.1
+        GATEWAY=
+        SWITCH=ovsbr0
+        if [ -n "$TAP" ];then
+                ifconfig $TAP up
+                ifconfig $SWITCH down &>/dev/null
+                ovs-vsctl del-br $SWITCH
+                ovs-vsctl add-br $SWITCH
+                ifconfig $ETH0 0.0.0.0
+                ifconfig $SWITCH $IP up netmask $NETMASK
+                #-- external access not required for this test.
+                #route add default gw $GATEWAY
+                ovs-vsctl add-port $SWITCH $ETH0
+                ovs-vsctl add-port $SWITCH $TAP
+                exit 0
+        else
+                echo "$0: No tap device"
+                exit 1
+        fi
+
+Start Qemu
+==========
+This example will bring up qemu with a tap network interface.
+Note: this command must be run as root due to the networking setup.
+
+        $ qemu-system-x86_64 -nographic -k en-us -m 1024  \
+                -net nic,macaddr=1a:46:0b:ca:bc:7a,model=virtio \
+                -net tap -enable-kvm\
+                -kernel /opt/dpdk-guest-kernel \
+                -append 'root=/dev/vda ro console=ttyS0' \
+                -drive file=/opt/intel-xeon-core-ovp-kvm-preempt-rt-dist.ext3,cache=none,if=virtio
+
+Once the guest OS is up and running, configure the quest network interface:
+        $ ifconfig eth0 192.168.1.10
+
+Ping the bridge:
+        $ ping 192.168.1.1
+
+From the host, view the bridged network:
+$ ovs-vsctl show
+c1212b96-ef49-4a8e-b598-09b05b854dd0
+    Bridge "ovsbr0"
+        Port "tap0"
+            Interface "tap0"
+        Port "eth1"
+            Interface "eth1"
+        Port "ovsbr0"
+            Interface "ovsbr0"
+                type: internal
+
+At this point, openvswitch is up and running.  If you want external
+network access, you need to set a GATEWAY in the qemu-ifup script and
+make sure the external device is part of the bridge.
+
+Note:
+Proper setup will require a /etc/qemu-ifdown script to tear down the
+bridge and interfaces. (not provided here).