Ceilometer component in
OpenStack is a great project for me to study further in depth I think. I am not going to introduce it because it's not the scope of this post. Instead, I only want to list some resources about
Ceilometer to collect the bandwith/traffic accounting of
Neutron L3 router.
From this
offical document: https://wiki.openstack.org/wiki/Neutron/Metering/Bandwidth
we can know that the actual implementation to collect the bandwidth of
Neutron L3 router is based on
iptables.
We can use the neutron command to list the related metering rules and labels
$ neutron meter-label-list
$ neutron meter-label-rule-list
The "neutron-meter-agent" will collect the traffic accounting in the
iptables chain and push to
oslo-messaging. So the following command can show the traffic accounting in
Neutron L3 router
root@sn1
:~# nova --
os-project-name
mickey list
root@sn1
:~# nova show bb1879bd-1202-4007-9376-41be30e07ae9
root@sn1
:~# neutron --
os-tenant-name
mickey router-list
root@node-5
:~# neutron meter-label-rule-list
root@node-5
:~# neutron meter-label-rule-show d31f0b9e-8824-4857-a2dc-19f237723f0c
root@node-5
:~# neutron meter-label-rule-show 1ae289ef-687e-4303-8036-9a7566dd5365
So, we need to find the metering labels: "neutron-meter-l-78675a84" and "neutron-meter-l-b88c5977"
root@cn3:~# ip netns exec qrouter-b1741371-ee12-46a1-831b-d3b35429d7c8 iptables -nL -v -x
root@cn3:~# ip netns exec qrouter-b1741371-ee12-46a1-831b-d3b35429d7c8 iptables -t nat -S
Here is the example to query the metering data in Ceilometer
$ root@node-5:~# ceilometer statistics -m bandwidth -q "resource=b88c5977-4445-4f19-9c8f-3d92809f844e;timestamp>=2016-03-01T00:00:00" --period 86400
P.S:
The following article is to introduce "Traffic Accounting with Linux IPTables" which can make us
more understand it.
http://www.catonmat.net/blog/traffic-accounting-with-iptables/
https://wiki.openstack.org/wiki/Neutron/Metering/Bandwidth
