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Example: memory buffers collectd exec plugin
Example: memory buffers collectd exec plugin
The following custom collectd exec plugin uses Bash and the used/free buffers values from the Linux command, free.
RightScript: Install memory_buffers collectd plugin
Create a RightScript with the following code and ensure that you set SERVER_UUID as an input with a dropdown default value of RS_INSTANCE_UUID.
#!/bin/bash -e
interval=20
# Determine the collectd plugin path, based on the architecture of the machine.
collectd_dir="/usr/lib/collectd"
[ "$(uname -m)" == "x86_64" ] && collectd_dir="/usr/lib64/collectd"
# Create the plugin directory if needed, and copy the script into it.
mkdir -p "$collectd_dir"/plugins
cp -f "$RS_ATTACH_DIR"/memory_buffers.bash "$collectd_dir"/plugins/memory_buffers.bash
chmod +x "$collectd_dir"/plugins/memory_buffers.bash
chmod 775 "$collectd_dir"/plugins/memory_buffers.bash
if [ "$RS_DISTRO" = 'ubuntu' ]; then
config="/etc/collectd/collectd.conf"
plugin_dir="/etc/collectd/conf"
elif [ "$RS_DISTRO" = 'centos' ]; then
config="/etc/collectd.conf"
plugin_dir="/etc/collectd.d"
fi
exec_plugin_conf="$plugin_dir/memory_buffers.conf"
if ! grep memory_buffers "$exec_plugin_conf" >/dev/null 2>&1; then
cat <<EOF>> $exec_plugin_conf
<Plugin exec>
# userid plugin executable plugin args
Exec "nobody" "$collectd_dir/plugins/memory_buffers.bash" "$SERVER_UUID" "$interval"
</Plugin>
EOF
fi
/etc/init.d/collectd restart
echo 'Done.' memory_buffers.bash
Copy and paste the following into a new text file on your computer. Save it as memory_buffers.bash and upload it as an attachment to the RightScript.
: ${id:="$SERVER_UUID"}
: ${id:="$1"}
: ${id:=$(< /var/spool/ec2/meta-data/instance-id)}
while true; do
start_run=$(date +%s)
data_used=$(free | grep "buffers/cache" | awk '{ print $3 }')
data_free=$(free | grep "buffers/cache" | awk '{ print $4 }')
echo 'PUTVAL '"$id"'/memory_buffers/gauge-used '"$start_run"':'"$data_used"
echo 'PUTVAL '"$id"'/memory_buffers/gauge-free '"$start_run"':'"$data_free"
sleep 10
done Example output of plugin
After you running the RightScript on the server successfully, its also possible to test it manually within shell:
root@sandbox:~# "/usr/lib/collectd/plugins/memory_buffers.bash" "00-0BIJPUB"PUTVAL 00-0BIJPUB/memory_buffers/gauge-used 1299043002:99288PUTVAL 00-0BIJPUB/memory_buffers/gauge-free 1299043002:1606424PUTVAL 00-0BIJPUB/memory_buffers/gauge-used 1299043012:99380PUTVAL 00-0BIJPUB/memory_buffers/gauge-free 1299043012:1606292PUTVAL 00-0BIJPUB/memory_buffers/gauge-used 1299043022:99364PUTVAL 00-0BIJPUB/memory_buffers/gauge-free 1299043022:1606308
Example Alert Specification
Add an alert to your ServerTemplate, such as:
if memory_buffers/gauge-free.value < '100' for 1 min then escalate to 'critical'
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