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Fix docs

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Signed-off-by: Miek Gieben <miek@miek.nl>
This commit is contained in:
Miek Gieben
2020-07-09 22:02:07 +02:00
parent 29acaf739e
commit 45ff6dd1c4
1 changed files with 2 additions and 16 deletions
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18
plugin/traffic/README.md
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@@ -101,15 +101,11 @@ When a cluster is named this usually consists out of a single word, i.e. "cluste
The *traffic* plugins uses the name(s) specified in the Server Block to create fully qualified The *traffic* plugins uses the name(s) specified in the Server Block to create fully qualified
domain names. For example if the Server Block specifies `lb.example.org` as one of the names, domain names. For example if the Server Block specifies `lb.example.org` as one of the names,
and "cluster-v0" is one of the load balanced cluster, *traffic* will respond to queries asking for and "cluster-v0" is one of the load balanced cluster, *traffic* will respond to queries asking for
`cluster-v0.lb.example.org.` and the same goes for `web`; `web.lb.example.org`. `cluster-v0.lb.example.org.` and the same goes for "web"; `web.lb.example.org`.
For SRV queries all endpoints are returned, the SRV target names are synthesized: For SRV queries all endpoints are returned, the SRV target names are synthesized:
`endpoint-<N>.web.lb.example.org` to take the example from above. *N* is an integer starting with 0. `endpoint-<N>.web.lb.example.org` to take the example from above. *N* is an integer starting with 0.
The gRPC load balancer name: `_grpclb._tcp.<cluster>.<zone>` will also be resolved in the same way
as normal SRV queries. gRPC uses this to find load balancers. Note that the addresses returned in
this care are from the management cluster.
## Matching Algorithm ## Matching Algorithm
How are clients match against the data we receive from xDS endpoint? How are clients match against the data we receive from xDS endpoint?
@@ -150,7 +146,7 @@ This will load balance any names under `lb.example.org` using the data from the
localhost on port 18000. The node ID will be `test-id` and no TLS will be used. Assuming a localhost on port 18000. The node ID will be `test-id` and no TLS will be used. Assuming a
management server returns config for `web` cluster, you can query CoreDNS for it, below we do an management server returns config for `web` cluster, you can query CoreDNS for it, below we do an
address lookup, which returns an address for the endpoint. The second example shows a SRV lookup address lookup, which returns an address for the endpoint. The second example shows a SRV lookup
which returns all endpoints. The third shows what gRPC will ask for when looking for load balancers. which returns all endpoints.
~~~ sh ~~~ sh
$ dig web.lb.example.org +noall +answer $ dig web.lb.example.org +noall +answer
@@ -164,16 +160,6 @@ web.lb.example.org. 5 IN SRV 100 100 18008 endpoint-2.web.lb.example.org.
endpoint-0.web.lb.example.org. 5 IN A 127.0.1.1 endpoint-0.web.lb.example.org. 5 IN A 127.0.1.1
endpoint-1.web.lb.example.org. 5 IN A 127.0.1.2 endpoint-1.web.lb.example.org. 5 IN A 127.0.1.2
endpoint-2.web.lb.example.org. 5 IN A 127.0.2.1 endpoint-2.web.lb.example.org. 5 IN A 127.0.2.1
$ dig _grpclb._tcp.web.lb.example.org SRV +noall +answer +additional
_grpclb._tcp.web.lb.example.org. 5 IN SRV 100 100 18008 endpoint-0.xds.lb.example.org.
_grpclb._tcp.web.lb.example.org. 5 IN SRV 100 100 18008 endpoint-1.xds.lb.example.org.
_grpclb._tcp.web.lb.example.org. 5 IN SRV 100 100 18008 endpoint-2.xds.lb.example.org.
endpoint-0.xds.lb.example.org. 5 IN A 10.0.1.1
endpoint-1.xds.lb.example.org. 5 IN A 10.0.1.2
endpoint-2.xds.lb.example.org. 5 IN A 10.0.2.1
~~~ ~~~
## Bugs ## Bugs