graphite-dev team mailing list archive

[chrismd <question140480@xxxxxxxxxxxxxxxxxxxxx>]

Question #140480 on Graphite changed:
https://answers.launchpad.net/graphite/+question/140480

chrismd proposed the following answer:
That's correct, when a metric lives on a particular graphite server
*all* datapoints for that metric need to be sent to that server. If you
want the metric to be on 2 servers then all datapoints for it need to go
to both servers. When you request a graph from a webapp it first checks
to see if it has the metric data locally and if it does not it queries
the other servers in the cluster, the first to respond that it has the
metric then gets queried for whatever datapoints it has. So if you're
sending some datapoints to server A and some to server B, your graph may
contain the data from either server but not both, hence both servers
need to have the complete set of datapoints.

The way to ensure your datapoints all end up on the right servers is by
using carbon-relay.py and defining rules that consistently map metrics
to the servers. All clients sending data to graphite should send their
data to the carbon-relay and not to carbon-cache. The carbon-relay will
apply the rules and then forward the datapoints on to the appropriate
carbon-cache instances. An example relay-rules.conf is shown on the
question page you referenced. Let me know if you need more clarification
about configuring the relay.

-- 
You received this question notification because you are a member of
graphite-dev, which is an answer contact for Graphite.