InFlightReq¶
Limiting the Number of Simultaneous In-Flight Requests
To proactively prevent services from being overwhelmed with high load, a limit on the number of simultaneous in-flight requests can be applied.
Configuration Examples¶
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.amount=10"
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: test-inflightreq
spec:
inFlightReq:
amount: 10
# Limiting to 10 simultaneous connections
- "traefik.http.middlewares.test-inflightreq.inflightreq.amount=10"
"labels": {
"traefik.http.middlewares.test-inflightreq.inflightreq.amount": "10"
}
# Limiting to 10 simultaneous connections
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.amount=10"
# Limiting to 10 simultaneous connections
[http.middlewares]
[http.middlewares.test-inflightreq.inFlightReq]
amount = 10
# Limiting to 10 simultaneous connections
http:
middlewares:
test-inflightreq:
inFlightReq:
amount: 10
Configuration Options¶
amount
¶
The amount
option defines the maximum amount of allowed simultaneous in-flight request.
The middleware will return an HTTP 429 Too Many Requests
if there are already amount
requests in progress (based on the same sourceCriterion
strategy).
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.amount=10"
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: test-inflightreq
spec:
inFlightReq:
amount: 10
# Limiting to 10 simultaneous connections
- "traefik.http.middlewares.test-inflightreq.inflightreq.amount=10"
"labels": {
"traefik.http.middlewares.test-inflightreq.inflightreq.amount": "10"
}
# Limiting to 10 simultaneous connections
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.amount=10"
# Limiting to 10 simultaneous connections
[http.middlewares]
[http.middlewares.test-inflightreq.inFlightReq]
amount = 10
# Limiting to 10 simultaneous connections
http:
middlewares:
test-inflightreq:
inFlightReq:
amount: 10
sourceCriterion
¶
SourceCriterion defines what criterion is used to group requests as originating from a common source.
The precedence order is ipStrategy
, then requestHeaderName
, then requestHost
.
If none are set, the default is to use the requestHost
.
sourceCriterion.ipStrategy
¶
The ipStrategy
option defines two parameters that sets how Traefik will determine the client IP: depth
, and excludedIPs
.
ipStrategy.depth
¶
The depth
option tells Traefik to use the X-Forwarded-For
header and take the IP located at the depth
position (starting from the right).
- If
depth
is greater than the total number of IPs inX-Forwarded-For
, then the client IP will be empty. depth
is ignored if its value is lesser than or equal to 0.
Example of Depth & X-Forwarded-For
If depth
was equal to 2, and the request X-Forwarded-For
header was "10.0.0.1,11.0.0.1,12.0.0.1,13.0.0.1"
then the "real" client IP would be "10.0.0.1"
(at depth 4) but the IP used as the criterion would be "12.0.0.1"
(depth=2
).
X-Forwarded-For |
depth |
clientIP |
---|---|---|
"10.0.0.1,11.0.0.1,12.0.0.1,13.0.0.1" |
1 |
"13.0.0.1" |
"10.0.0.1,11.0.0.1,12.0.0.1,13.0.0.1" |
3 |
"11.0.0.1" |
"10.0.0.1,11.0.0.1,12.0.0.1,13.0.0.1" |
5 |
"" |
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.ipstrategy.depth=2"
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: test-inflightreq
spec:
inFlightReq:
sourceCriterion:
ipStrategy:
depth: 2
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.ipstrategy.depth=2"
"labels": {
"traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.ipstrategy.depth": "2"
}
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.ipstrategy.depth=2"
[http.middlewares]
[http.middlewares.test-inflightreq.inflightreq]
[http.middlewares.test-inflightreq.inFlightReq.sourceCriterion.ipStrategy]
depth = 2
http:
middlewares:
test-inflightreq:
inFlightReq:
sourceCriterion:
ipStrategy:
depth: 2
ipStrategy.excludedIPs
¶
excludedIPs
tells Traefik to scan the X-Forwarded-For
header and pick the first IP not in the list.
If depth
is specified, excludedIPs
is ignored.
Example of ExcludedIPs & X-Forwarded-For
X-Forwarded-For |
excludedIPs |
clientIP |
---|---|---|
"10.0.0.1,11.0.0.1,12.0.0.1,13.0.0.1" |
"12.0.0.1,13.0.0.1" |
"11.0.0.1" |
"10.0.0.1,11.0.0.1,12.0.0.1,13.0.0.1" |
"15.0.0.1,13.0.0.1" |
"12.0.0.1" |
"10.0.0.1,11.0.0.1,12.0.0.1,13.0.0.1" |
"10.0.0.1,13.0.0.1" |
"12.0.0.1" |
"10.0.0.1,11.0.0.1,12.0.0.1,13.0.0.1" |
"15.0.0.1,16.0.0.1" |
"13.0.0.1" |
"10.0.0.1,11.0.0.1" |
"10.0.0.1,11.0.0.1" |
"" |
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.ipstrategy.excludedips=127.0.0.1/32, 192.168.1.7"
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: test-inflightreq
spec:
inFlightReq:
sourceCriterion:
ipStrategy:
excludedIPs:
- 127.0.0.1/32
- 192.168.1.7
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.ipstrategy.excludedips=127.0.0.1/32, 192.168.1.7"
"labels": {
"traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.ipstrategy.excludedips": "127.0.0.1/32, 192.168.1.7"
}
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.ipstrategy.excludedips=127.0.0.1/32, 192.168.1.7"
[http.middlewares]
[http.middlewares.test-inflightreq.inflightreq]
[http.middlewares.test-inflightreq.inFlightReq.sourceCriterion.ipStrategy]
excludedIPs = ["127.0.0.1/32", "192.168.1.7"]
http:
middlewares:
test-inflightreq:
inFlightReq:
sourceCriterion:
ipStrategy:
excludedIPs:
- "127.0.0.1/32"
- "192.168.1.7"
sourceCriterion.requestHeaderName
¶
Requests having the same value for the given header are grouped as coming from the same source.
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.requestheadername=username"
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: test-inflightreq
spec:
inFlightReq:
sourceCriterion:
requestHeaderName: username
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.requestheadername=username"
"labels": {
"traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.requestheadername": "username"
}
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.requestheadername=username"
[http.middlewares]
[http.middlewares.test-inflightreq.inflightreq]
[http.middlewares.test-inflightreq.inFlightReq.sourceCriterion]
requestHeaderName = "username"
http:
middlewares:
test-inflightreq:
inFlightReq:
sourceCriterion:
requestHeaderName: username
sourceCriterion.requestHost
¶
Whether to consider the request host as the source.
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.requesthost=true"
apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
name: test-inflightreq
spec:
inFlightReq:
sourceCriterion:
requestHost: true
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.requesthost=true"
"labels": {
"traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.requesthost": "true"
}
labels:
- "traefik.http.middlewares.test-inflightreq.inflightreq.sourcecriterion.requesthost=true"
[http.middlewares]
[http.middlewares.test-inflightreq.inflightreq]
[http.middlewares.test-inflightreq.inFlightReq.sourceCriterion]
requestHost = true
http:
middlewares:
test-inflightreq:
inFlightReq:
sourceCriterion:
requestHost: true