Merge pull request #549 from bogdando/fix_ha_lb

Update ha docs
This commit is contained in:
Smaine Kahlouch 2016-10-17 15:45:35 +02:00 committed by GitHub
commit 1de127470f

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@ -49,9 +49,11 @@ type. The following diagram shows how traffic to the apiserver is directed.
![Image](figures/loadbalancer_localhost.png?raw=true)
..note:: Kubernetes master nodes still use insecure localhost access because
Note: Kubernetes master nodes still use insecure localhost access because
there are bugs in Kubernetes <1.5.0 in using TLS auth on master role
services.
services. This makes backends receiving unencrypted traffic and may be a
security issue when interconnecting different nodes, or maybe not, if those
belong to the isolated management network without external access.
A user may opt to use an external loadbalancer (LB) instead. An external LB
provides access for external clients, while the internal LB accepts client
@ -81,24 +83,19 @@ loadbalancer_apiserver:
This domain name, or default "lb-apiserver.kubernetes.local", will be inserted
into the `/etc/hosts` file of all servers in the `k8s-cluster` group. Note that
the HAProxy service should as well be HA and requires a VIP management, which
is out of scope of this doc.
is out of scope of this doc. Specifying an external LB overrides any internal
localhost LB configuration.
Specifying an external LB overrides any internal localhost LB configuration.
Note that for this example, the `kubernetes-apiserver-http` endpoint
has backends receiving unencrypted traffic, which may be a security issue
when interconnecting different nodes, or maybe not, if those belong to the
isolated management network without external access.
In order to achieve HA for HAProxy instances, those must be running on the
each node in the `k8s-cluster` group as well, but require no VIP, thus
no VIP management.
Note: In order to achieve HA for HAProxy instances, those must be running on
the each node in the `k8s-cluster` group as well, but require no VIP, thus
no VIP management.
Access endpoints are evaluated automagically, as the following:
| Endpoint type | kube-master | non-master |
|------------------------------|---------------|---------------------|
| Local LB | http://lc:p | http://lc:sp |
| External LB, no internal | http://lc:p | https://lb:lp |
| Local LB | http://lc:p | https://lc:sp |
| External LB, no internal | https://lb:lp | https://lb:lp |
| No ext/int LB (default) | http://lc:p | https://m[0].aip:sp |
Where: