Merge "Add option to setup netconsole to remote destination"

devstack-vm-gate-wrap.sh

@@ -400,6 +400,27 @@ export DEVSTACK_GATE_TOPOLOGY=${DEVSTACK_GATE_TOPOLOGY:-aio}
 # for jobs that know exactly which repos they need.
 export DEVSTACK_GATE_PROJECTS_OVERRIDE=${DEVSTACK_GATE_PROJECTS_OVERRIDE:-""}
 
+# Set this to enable remote logging of the console via UDP packets to
+# a specified ipv4 ip:port (note; not hostname -- ip address only).
+# This can be extremely useful if a host is oopsing or dropping off
+# the network amd you are not getting any useful logs from jenkins.
+#
+# To capture these logs, enable a netcat/socat type listener to
+# capture UDP packets at the specified remote ip.  For example:
+#
+#  $ nc -v -u -l -p 6666 | tee save-output.log
+# or
+#  $ socat udp-recv:6666 - | tee save-output.log
+#
+# One further trick is to send interesting data to /dev/ksmg; this
+# data will get out over the netconsole even if the main interfaces
+# have been disabled, etc.  e.g.
+#
+#  $ ip addr | sudo tee /dev/ksmg
+#
+export DEVSTACK_GATE_NETCONSOLE=${DEVSTACK_GATE_NETCONSOLE:-""}
+enable_netconsole
+
 if [ -n "$DEVSTACK_GATE_PROJECTS_OVERRIDE" ]; then
     PROJECTS=$DEVSTACK_GATE_PROJECTS_OVERRIDE
 fi

functions.sh

@@ -864,6 +864,45 @@ function remote_copy_file {
     scp $ssh_opts "$src" "$dest"
 }
 
+# enable_netconsole
+function enable_netconsole {
+
+    # do nothing if not set
+    if [[ $DEVSTACK_GATE_NETCONSOLE = "" ]]; then
+        return
+    fi
+
+    local remote_ip=$(echo $DEVSTACK_GATE_NETCONSOLE | awk -F: -e '{print $1}')
+    local remote_port=$(echo $DEVSTACK_GATE_NETCONSOLE | awk -F: -e '{print $2}')
+
+    # netconsole requires the device to send and the destitation MAC,
+    # which is obviously on the same subnet.  The way to get packets
+    # out to the world is specify the default gw as the remote
+    # destination.
+    local default_gw=$(ip route | grep default | awk '{print $3}')
+    local gw_mac=$(arp $default_gw | grep $default_gw | awk '{print $3}')
+    local gw_dev=$(ip route | grep default | awk '{print $5}')
+
+    # turn up message output
+    sudo dmesg -n 8
+
+    sudo modprobe configfs
+    sudo modprobe netconsole
+
+    sudo mount none -t configfs /sys/kernel/config
+
+    sudo mkdir /sys/kernel/config/netconsole/target1
+
+    pushd /sys/kernel/config/netconsole/target1
+    echo "$gw_dev" | sudo tee ./dev_name
+    echo "$remote_ip" | sudo tee ./remote_ip
+    echo "$gw_mac" | sudo tee ./remote_mac
+    echo "$remote_port" | sudo tee ./remote_port
+    echo 1 | sudo tee ./enabled
+    popd
+}
+
+
 # This function creates an internal gre bridge to connect all external
 # network bridges across the compute and network nodes.
 # bridge_name: Bridge name on each host for logical l2 network