docker
/
docs
mirror of https://github.com/docker/docs.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Update DTR requirements for load balancers (#72) 

* Update DTR requirements for load balancers

* Remove references to /health
This commit is contained in:
Joao Fernandes 2017-05-09 11:27:00 -07:00 committed by Jim Galasyn
parent a9ed01a471
commit 7f1bbd78f2
2 changed files with 11 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
datacenter/dtr/2.3/guides/admin/configure/use-a-load-balancer.md
View File

@ -23,20 +23,22 @@ or cloud-based load balancer to balance requests across multiple DTR replicas.
Make sure you configure your load balancer to:
* Load balance TCP traffic on ports 80 and 443
* Not terminate HTTPS connections
* Use the unauthenticated `/health` endpoint (note the lack of an `/api/v0/` in
* Make sure the load balancer is not buffering requests
* Make sure the load balancer is forwarding the `Host` HTTP header correctly
* Make sure there's no timeout for idle connections, or set it to more than 10 minutes
* Use the unauthenticated `/_ping` endpoint (note the lack of an `/api/v0/` in
the path) on each DTR replica, to check if the replica is healthy and if it
should remain in the load balancing pool or not
## Health check endpoints
The `/health` endpoint returns a JSON object for the replica being queried of
The `/_ping` endpoint returns a JSON object for the replica being queried of
the form:
```json
{
"Error": "error message",
"Health": true
"Healthy": true
}
```
@ -81,7 +83,7 @@ individually at the time specified in the `"replica_timestamp"` object.
The response also contains information about the internal DTR storage state,
which is around 45 KB of data. This, combined with the fact that the endpoint
requires admin credentials, means it is not particularly appropriate for load
balance checks. Use `/health` instead for those kinds of checks.
balance checks. Use `/_ping` instead for those kinds of checks.
## Configuration examples
@ -164,13 +166,13 @@ backend dtr_stats
stats refresh 5m
backend dtr_upstream_servers_80
mode tcp
option httpchk GET /health HTTP/1.1\r\nHost:\ <DTR_FQDN>
option httpchk GET /_ping HTTP/1.1\r\nHost:\ <DTR_FQDN>
server node01 <DTR_REPLICA_1_IP>:80 check weight 100
server node02 <DTR_REPLICA_2_IP>:80 check weight 100
server node03 <DTR_REPLICA_N_IP>:80 check weight 100
backend dtr_upstream_servers_443
mode tcp
option httpchk GET /health HTTP/1.1\r\nHost:\ <DTR_FQDN>
option httpchk GET /_ping HTTP/1.1\r\nHost:\ <DTR_FQDN>
server node01 <DTR_REPLICA_1_IP>:443 weight 100 check check-ssl verify none
server node02 <DTR_REPLICA_2_IP>:443 weight 100 check check-ssl verify none
server node03 <DTR_REPLICA_N_IP>:443 weight 100 check check-ssl verify none
@ -200,7 +202,7 @@ backend dtr_upstream_servers_443
"HealthCheck": {
"HealthyThreshold": 2,
"Interval": 10,
"Target": "HTTPS:443/health",
"Target": "HTTPS:443/_ping",
"Timeout": 2,
"UnhealthyThreshold": 4
},

2
datacenter/dtr/2.3/guides/admin/monitor-and-troubleshoot/index.md
View File

@ -29,7 +29,7 @@ resources, and logs.
DTR also exposes several endpoints you can use to assess if a DTR replica
is healthy or not:
* `/health`: Checks if the several components of a DTR replica are healthy, and
* `/_ping`: Checks if the DTR replica is healthy, and
returns a simple json response. This is useful for load balancing or other
automated health check tasks.
* `/nginx_status`: Returns the number of connections being handled by the