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Home Page: https://cloudprober.org
License: Apache License 2.0
[Moved to cloudprober/cloudprober] An active monitoring software to detect failures before your customers do.
Home Page: https://cloudprober.org
License: Apache License 2.0
Cloudprober's metrics package should support histograms value types.
at the github.com/google/cloudprober/cmd/BUILD file, in the past
filegroup(
name = "certs",
srcs = [
"ca-certificates.crt",
],
)
but now it has been removed, is it not needed?
Hunting around the code for a solution to an issue, I discovered the "/config" endpoint.
This is a useful endpoint for confirming cloudprober's current configuration.
Please consider including it (I think it's not currently) in the documentation.
Filing a retrospective issue:
Ping probe didn't honor the "latency_distribution" directive in the probe configuration. This was fixed by the commit 191b661.
Hi,
@manugarg
We are trying to replace the existing BB exporter with cloudprober now. We were able to test the DNS and HTTP probes.
But when we try to test PING probe, it is not working as expected. Can you please assist/tell if something is wrong with my cloudprober.cfg
probe {
name: "test_ping_job"
type: PING
targets {
gce_targets {
instances {}
}
}
run_on: "{{"123456.bnymellon.com"}}"
interval_msec: 12000 # 5s
timeout_msec: 6000 # 5s
}
It would be useful if the HTTP probe was extended to supported the following:
GET
, POST
, PUT
, HEAD
, DELETE
, PATCH
, OPTIONS
).Being able to customize HTTP requests in these ways would allow for a more comprehensive probe into a system in line with normal user behavior.
Improve ping probe tests to cover cases like the one reported in: #225.
Hi,
I see a metric named latency. just wanted to know if that latency metric is actually - latency of the cloudprober or from the network.
Also after adding/updating the URL in the cloudprober.cfg, is there anyway to reload it on the run-time. Every-time after making the changes in the file, i am re-starting the container.
Can someone advise ?
Thanks
Example failure:
https://travis-ci.org/google/cloudprober/jobs/484066432
It's mostly TestLossAndDelayed test that fails. Failure is mostly due to failing to receive expected number of packets:
udp_test.go:339: Case(delayed_2): p.res[].delayed=9, want 10
udp_test.go:339: Case(delayed_2): p.res[].delayed=9, want 10
We could do it in two ways:
a) Define targets independently of the probes and assign each one of them a unique id. Then in the probe definition refer to that id.
targets {
id: "vm-private-ip"
gce_targets {
}
}
probe {
name: "vm-to-vm"
type: PING
targets_id: "vm-private-ip"
ping_probe {
}
}
b) Introduce the concept of probeset where a probeset is a set of probes that use the same targets.
probeset {
targets {
..
}
probe {}
probe {}
}
In the docs only the code is linked, and since I'm not familiar with protobuff / go it didn't really help me.. my naiv approach was sth like this:
probe {
name: "cloudprober"
type: HTTP
targets {
host_names: "google.de"
}
interval_msec: 5000 # 5s
timeout_msec: 1000 # 1s
relative_url: "/"
}
but that already doesnt work, the config files also don't have a property for sth like "AbstractSpecialProbeConfig" and / or there is no inheritance, so where should I put the property? (maybe sth. for the docs?)
also adding more then 1 HTTP Probe only worked via host_names: "host1.de, host2.de" which was also not very clear for me (I guess it only matches against the first probe of a type it finds?)
Assuming #88, it's possible to deploy cloudprober
to Kubernetes and reference a custom config through Kubernetes' ConfigMap
:
Assuming cloudconfig.google.cfg
, per the documentation example, this can be uploaded to Kubernetes as a configuration file accessible as cloudconfig.cfg
:
kubectl create configmap cloudprober-config \
--from-file=cloudprober.cfg=cloudprober.google.cfg \
--namespace=default
or:
apiVersion: v1
data:
cloudprober.cfg: |
probe {
name: "google"
type: HTTP
targets {
host_names: "www.google.com"
}
interval_msec: 15000 # 15s
timeout_msec: 1000 # 1s
}
kind: ConfigMap
metadata:
name: cloudprober-config
namespace: default
NB Rename "cloudprober.cfg" in both as appropriate.
and:
kubectl describe configmaps/cloudprober-config \
--namespace=default
yields:
Name: cloudprober-config
Namespace: default
Labels: <none>
Annotations: <none>
Data
====
cloudprober.cfg:
----
probe {
name: "google"
type: HTTP
targets {
host_names: "www.google.com"
}
interval_msec: 15000 # 15s
timeout_msec: 1000 # 1s
}
Then:
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: cloudprober
spec:
replicas: 1
template:
metadata:
labels:
app: cloudprober
spec:
volumes:
- name: cloudprober-config
configMap:
name: cloudprober-config
containers:
- name: cloudprober
image: cloudprober/cloudprober
args: [
"--config_file","/cfg/cloudprober.cfg",
"--logtostderr"
]
volumeMounts:
- name: cloudprober-config
mountPath: /cfg
ports:
- name: http
containerPort: 9313
env:
- name: CLOUDPROBER_PORT
value: "9313"
---
apiVersion: v1
kind: Service
metadata:
name: cloudprober
labels:
app: cloudprober
spec:
ports:
- port: 9313
protocol: TCP
targetPort: 9313
selector:
app: cloudprober
type: NodePort
For some reason, under Kubernetes, cloudprober
balks if CLOUDPROBER_PORT
is not set.
It should be easy to add a surfacer for InfluxDB. InfluxDB measurements correspond to EventMetrics (EM) in cloudprober. "tag keys" and "tag values" correspond to EM labels, and "field keys" and "field values" correspond to EM metrics.
It will be useful to add a gRPC service to cloudprober that will allow on-demand probe execution.
Hi,
we are considering usage of Cloudprober in our organization as a part of ErrorBudget tool. We would like to use it to gather metrics from Elastic (numbers of failed/succeeded requests etc.). Second metric source would be active probing services healthchecks. Implementing probe for Elastic shouldn't be a problem. And we can use http probe for healthchecks. But metrics can be changed by users as they add new or change their SLOs. Restarting whole Cloudprober every time metrics change will not work as we would lose too much data.
Do you think we can use Cloudprober for our use case? Is there any way to change configs only for a part of probes? We considered extending Cloudprober but it seems that we would have to rewrite a lot of code as all probes are using the same context.
Would #149 solve our problem? Are there plans to add it in foreseeable future?
Cloudprober currently supports automatic expansion of GCE targets. We should add support for AWS targets as well.
If you use Cloudprober, would you mind sharing how you use it[1]? This will help in two ways:
[1] - For example, do you use targets discovery? Which monitoring system do you integrate with -- prometheus, stackdriver, or something else entirely? Which probe types? Do you run it in a docker container or just a vanilla binary etc.
Would be nice to have reload
command to re-read configuration instead of restart main process.
Reference:
https://cloud.google.com/profiler/docs/profiling-go
Apparently profiler can add up-to 5% overhead. We can make it an optional feature.
This should be fairly straightforward. We should probably use:
https://github.com/DataDog/datadog-go
To help debugging any performance issues, cloudprober should export its runtime stats:
We can extend sysvar module and add another file that includes utilities to do all this.
When compiled for ARM, metrics values are overflowing when they are cast from float64 to int. This seems to be caused by ARM using int32 instead of int64 during the conversion. This results in high-value metrics getting set to either 2147483.647 or 0 (depending on which GOARM value is used) as soon as the value overflows int32.
The code causing this:
Lines 92 to 95 in 882d33f
This can be fixed in a few ways:
I implemented the fourth option on an incoming pull request. Let me know if you'd prefer a different version of the fix.
A meaningful prefix, e.g. cloudprober_, would help to distinguish the cloudprober metrics from other metrics. It should be prepended to all stats, automatically.
While creating grafana dashboards for cloudprober metrics are not very hard, I would personally really enjoy seeing how other people view cloudprobers output. I was hoping that someone already had a grafana prometheus dashboard that they would be OK with publishing?
Thank you
cloudprober write data in prometheus surfacer end with timstamps, but in some cases, prometheus can't accept, error like:
msg="Error on ingesting samples that are too old or are too far into the future"
like Ben Kochie said in https://groups.google.com/d/msg/prometheus-users/NvLGxFZczJk/8hlYoAEsCwAJ
It's recommended to omit the timestamp. The timestamp in the spec is there to allow for federation or importing of data from external TDSBs
Should we delete the timestamp?
how to for : external prober type for latency with dist metrics and dist timeunit.
My current org (and many previous places i've been a part of) have a need for a tool which can be used to drive synthetic transactions by applying an application level input on a schedule (much like registering a probe :p). This service could measure latency/success of message processing (with a timeout). In my head this service is different from a probe as it would potentially need to support many different application level protocols ie (send a message over cloud pub/sub, kakfa, nsq, sqs, grpc, http/json, etc)
I was imagining that the input would contain a unique id for each synthetic transaction and when the target service is finished processing it would make an RPC call with the transaction status back to this service:
The reason I'm wondering about this in cloudprober is because cloudprober has all the pieces for something like this:
In order for something like above I imagine it would require some additional features like:
@manugarg I would love to hear your thoughts on synthetic transactions and if cloudprober might be a home for features like this?
We noticed that if HTTP probes are failing for some targets, it results in a disproportionate amount of increase in pending TCP connections and goroutines. Increase in number of goroutines (as reported by cloudprober's sysvars module) was almost about 45 times the number of failing HTTP targets.
I have used multiple HTTP probes with one cloudprober.
But, after some time, panic occurs. (about 30 minutes or 1 hour later)
Environment:
OS: CentOS 7.6.1810
Docker: 18.09.3
Cloudprober: v0.10.1
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x18 pc=0x4ee41c]
goroutine 45 [running]:
bufio.(*Writer).Flush(0xc00012f680, 0xc000434100, 0x68)
/home/travis/.gimme/versions/go1.11.linux.amd64/src/bufio/bufio.go:575 +0x5c
bufio.(*Writer).Write(0xc00012f680, 0xc000434100, 0x6a, 0x100, 0x1, 0x9, 0x3)
/home/travis/.gimme/versions/go1.11.linux.amd64/src/bufio/bufio.go:611 +0xeb
net/http.(*response).write(0xc0004c2000, 0x6a, 0xc000434100, 0x6a, 0x100, 0x0, 0x0, 0x15eebc0, 0x0, 0x0)
/home/travis/.gimme/versions/go1.11.linux.amd64/src/net/http/server.go:1551 +0x149
net/http.(*response).Write(0xc0004c2000, 0xc000434100, 0x6a, 0x100, 0x3, 0x3, 0x409813)
/home/travis/.gimme/versions/go1.11.linux.amd64/src/net/http/server.go:1521 +0x56
fmt.Fprintf(0xf65da0, 0xc0004c2000, 0xea1527, 0x9, 0xc00069be00, 0x3, 0x3, 0x6a, 0x0, 0x0)
/home/travis/.gimme/versions/go1.11.linux.amd64/src/fmt/print.go:189 +0xa5
github.com/google/cloudprober/surfacers/prometheus.New.func1(0xf65da0, 0xc0004c2000, 0xc000246300, 0xc0002e8a20, 0x56)
/home/travis/gopath/src/github.com/google/cloudprober/surfacers/prometheus/prometheus.go:131 +0x1bf
github.com/google/cloudprober/surfacers/prometheus.(*PromSurfacer).writeData(0xc0003ea120, 0xf65da0, 0xc0004c2000)
/home/travis/gopath/src/github.com/google/cloudprober/surfacers/prometheus/prometheus.go:360 +0x24d
github.com/google/cloudprober/surfacers/prometheus.New.func3(0xc0003ea120, 0xc0003ea180)
/home/travis/gopath/src/github.com/google/cloudprober/surfacers/prometheus/prometheus.go:150 +0x12c
created by github.com/google/cloudprober/surfacers/prometheus.New
/home/travis/gopath/src/github.com/google/cloudprober/surfacers/prometheus/prometheus.go:144 +0x1d7
Cloudprober is not able to capture the string values outputted by a script while running the script through cloudprober. Cloudprober at the moment can capture numerical values, an enhancement is needed to capture string values.
Is there any jitter configuration that we can use to avoid large amount of probes going to the same target simultaneously? Context: launching many cloudprober instances at the same time on various locations to probe the same set of targets.
We are using Cloudprober to ping ~20 hosts currently. From time to time it stops working, without crashing the container. The HTTP Endpoint still works, but there are no new results generated.
Hi all, I am a newbie. Help is appreciated. Thanks.
$ docker run --net host cloudprober/cloudprober
I0419 23:19:54.254899 1 cloudprober.go:130] Error reading config from metadata. Err: metadata: GCE metadata "project/attributes/cloudprober_config" not defined
W0419 23:19:54.255019 1 cloudprober.go:139] Config file /etc/cloudprober.cfg not found. Using default config.
I0419 23:19:54.306354 1 sysvars_gce.go:63] No instance_template found. Defaulting to undefined.
F0419 23:19:54.316272 1 cloudprober.go:178] Error initializing cloudprober. Err: error while creating listener for default HTTP server. Err: listen tcp :9313: bind: addr
ess already in use
On the current master branch (667a6db), when the setting use_datagram_socket: false
with multiple targets, the ping begins failing with the error packet too small: size (4) < minPacketSize (16)
. If two targets are specified, it seems like half of the packets start failing. If three or more targets are listed, no packets from the third+ targets will succeed.
This can be seen using this config:
probe {
name: "ping"
type: PING
targets {
host_names: "google.com, github.com"
}
ping_probe {
use_datagram_socket: false
}
}
The errors will be:
W0320 11:25:40.905329 5273 ping.go:339] packet too small: size (4) < minPacketSize (16)
W0320 11:25:41.875763 5273 ping.go:331] read ip4 0.0.0.0: i/o timeout
W0320 11:25:42.906471 5273 ping.go:339] packet too small: size (4) < minPacketSize (16)
W0320 11:25:43.874060 5273 ping.go:331] read ip4 0.0.0.0: i/o timeout
W0320 11:25:44.904014 5273 ping.go:339] packet too small: size (4) < minPacketSize (16)
W0320 11:25:45.874674 5273 ping.go:331] read ip4 0.0.0.0: i/o timeout
W0320 11:25:46.903673 5273 ping.go:339] packet too small: size (4) < minPacketSize (16)
W0320 11:25:47.874429 5273 ping.go:331] read ip4 0.0.0.0: i/o timeout
W0320 11:25:48.903609 5273 ping.go:339] packet too small: size (4) < minPacketSize (16)
W0320 11:25:49.873686 5273 ping.go:331] read ip4 0.0.0.0: i/o timeout
And the metrics will show:
#TYPE total counter
total{ptype="ping",probe="ping",dst="google.com"} 160
total{ptype="ping",probe="ping",dst="github.com"} 160
#TYPE success counter
success{ptype="ping",probe="ping",dst="google.com"} 160
success{ptype="ping",probe="ping",dst="github.com"} 80
It appears that the code is not successfully binding stdin
(stdout
, stderr
) to Cloudprober
.
I added some debugging and in external.go
sendRequest
p.cmdStdin
is <nil>
&{redis_probe server ./redis_probe [] 0xc4200b8a50 0xc42016cf60 0xc4200acdd0 0 map[] 1 false <nil> <nil> <nil> 0xc4200aa4e0 map[] map[:1] map[] 0xc4202bea00 map[] {0 0}}
The only place I have found where p.cmdStdin
is assigned is startCmdIfNotRunning
but I added a deubgging statement to this function and it appears not to be called. Additionally Cloudprober
reports Creating a EXTERNAL probe: redis_probe
but startCmdIfNotRunning
would say Starting external command
. The former appears generated by:
Line 155 in db05064
I tried using the redis example:
go run main.go
2018/04/04 16:04:00 hello=world
set_latency_ms 0.629330
get_latency_ms 0.474291
And after building it:
./redis-probe
2018/04/04 16:04:18 hello=world
set_latency_ms 0.889990
get_latency_ms 0.668944
And, if I set the cloudprober.cfg to mode: ONCE
it works:
cloudprober --config_file=./cloudprober.cfg --logtostderr --debug_log
Error while getting default lameduck lister, lameduck behavior will be disabled. Err: global lameduck service not initialized
Creating a EXTERNAL probe: redis-probe
Initialized prometheus exporter at the URL: /metrics
Running external command: ./redis-probe
1522883241 labels=ptype=external,probe=redis-probe,dst= success=1 total=1 latency=4325.327
1522883241 labels=ptype=external,probe=redis-probe,dst= set_latency_ms=1.032 get_latency_ms=0.83
cloudprober 1522883239827938228 1522883241 labels=ptype=external,probe=redis-probe,dst= success=1 total=1 latency=4325.327
cloudprober 1522883239827938229 1522883241 labels=ptype=external,probe=redis-probe,dst= set_latency_ms=1.032 get_latency_ms=0.83
Checking validity of new label: ptype
Checking validity of new label: probe
Checking validity of new label: dst
Checking validity of new metric: success
Checking validity of new metric: total
Checking validity of new metric: latency
Checking validity of new metric: set_latency_ms
Checking validity of new metric: get_latency_ms
BUT:
cloudprober --config_file=./cloudprober.cfg --logtostderr --debug_log
Error while getting default lameduck lister, lameduck behavior will be disabled. Err: global lameduck service not initialized
Creating a EXTERNAL probe: redis-probe
Initialized prometheus exporter at the URL: /metrics
Sending a probe request 1 to the external probe server for target
2018/04/04 16:09:19 [dazwilkin:sendRequest] &{redis-probe server ./redis-probe [] 0xc420188780 0xc420195440 0xc4200ac450 0 map[] 1 false <nil> <nil> <nil> 0xc4200aa5a0 map[] map[:1] map[] 0xc42018e980 map[] {0 0}}
2018/04/04 16:09:19 [dazwilkin:sendRequest] <nil>
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x18 pc=0x4c5077]
goroutine 47 [running]:
fmt.Fprintf(0x0, 0x0, 0xd21aa0, 0x17, 0xc42007bcd8, 0x2, 0x2, 0x82ce045d, 0xbea974a7e370a659, 0x1d)
/usr/lib/google-golang/src/fmt/print.go:189 +0x77
github.com/google/cloudprober/probes/external/serverutils.WriteMessage(0xd99d20, 0xc420184940, 0x0, 0x0, 0x1, 0x2)
/usr/local/google/home/dazwilkin/Projects/dazwilkin-180330-cloudprober/go/src/github.com/google/cloudprober/probes/external/serverutils/serverutils.go:96 +0x1c9
github.com/google/cloudprober/probes/external.(*Probe).sendRequest(0xc42030c000, 0xc400000001, 0xd13950, 0x0, 0xc4200b14d8, 0xc4200af770)
/usr/local/google/home/dazwilkin/Projects/dazwilkin-180330-cloudprober/go/src/github.com/google/cloudprober/probes/external/external.go:328 +0x641
github.com/google/cloudprober/probes/external.(*Probe).runServerProbe(0xc42030c000, 0xd9bce0, 0xc420195ce0, 0xc420195980)
/usr/local/google/home/dazwilkin/Projects/dazwilkin-180330-cloudprober/go/src/github.com/google/cloudprober/probes/external/external.go:403 +0x199
github.com/google/cloudprober/probes/external.(*Probe).runProbe(0xc42030c000, 0xd9bca0, 0xc4200ce000, 0xc420195980)
/usr/local/google/home/dazwilkin/Projects/dazwilkin-180330-cloudprober/go/src/github.com/google/cloudprober/probes/external/external.go:462 +0x103
github.com/google/cloudprober/probes/external.(*Probe).Start(0xc42030c000, 0xd9bca0, 0xc4200ce000, 0xc420195980)
/usr/local/google/home/dazwilkin/Projects/dazwilkin-180330-cloudprober/go/src/github.com/google/cloudprober/probes/external/external.go:478 +0x80
created by github.com/google/cloudprober.(*Prober).start
/usr/local/google/home/dazwilkin/Projects/dazwilkin-180330-cloudprober/go/src/github.com/google/cloudprober/cloudprober.go:248 +0x2b6
I had originally written my own trivial probe and tried it in server mode. When this didn't work (with the same results as above), I started working from the redis
sample.
Background
I'm endeavoring to deploy Cloudprober
(successfully) and probes (unsuccessfully) to Kubernetes. The approach requires both Cloudprober
and the probes to be containerized. In this model, it's preferable (necessary?) to have the probe run in server mode to avoid the waste of spooling up a probe container, making a singular measurement, terminating the container and then recreating another clone. IIUC this is the reasoning for the server mode probe too.
External prober should be able to retrieve external probe binary from remote location (GCS/S3/etc). This will allow for easy deployment of external probes.
UDP probe creates a new socket for each target. This can get expensive for large number of targets. We should change UDP probe to use the same socket for all targets, similar to what PING probe does.
To do this, we should probably use ListenUDP() to create a UDP socket that can send packets to multiple addresses:
https://golang.org/pkg/net/#ListenUDP
Please consider revising project's Dockerfile
to use ENTRYPOINT
(to start cloudprober
) and CMD
to default the flags to --logtostderr
like so:
...
ENTRYPOINT ["/cloudprober"]
CMD ["--logtostderr"]
Currently, the container does not permit e.g. arbitrary config files:
docker run \
--publish=9313:9313 \
--volume=$PWD/cloudprober.google.cfg:/cloudprober.cfg cloudprober/cloudprober \
--config_file /cloudprober.cfg \
--logtostderr
produces:
docker: Error response from daemon: oci runtime error: container_linux.go:265: starting container process caused "exec: \"--config_file\": executable file not found in $PATH".
ERRO[0000] error waiting for container: context canceled
With the change, the docker
command works.
This change helps e.g. run cloudprober
on Kubernetes
Is it possible to specify headers value in the cfg file ?
http_probe {
protocol: HTTPS
method: GET
relative_url: "/"
headers: {
name: "Content-Type"
value: "application/json"
}
It would be great if Cloudprober's HTTP probes could also do some simple regex-based response validation.
// Start starts the probe and writes back the data on the provided channel.
// Probe should have been initialized with Init() before calling Start on it.
func (p *Probe) Start(ctx context.Context, dataChan chan *metrics.EventMetrics) {
if p.conn == nil {
p.l.Critical("Probe has not been properly initialized yet.")
}
defer p.conn.close()
for ts := range time.Tick(p.opts.Interval) {
// Don't run another probe if context is canceled already.
select {
case <-ctx.Done():
return
default:
}
p.runProbe()
p.l.Debugf("%s: Probe finished.", p.name)
if (p.runCnt % uint64(p.c.GetStatsExportInterval())) != 0 {
continue
}
for _, t := range p.targets {
em := metrics.NewEventMetrics(ts).
AddMetric("total", metrics.NewInt(p.sent[t])).
AddMetric("success", metrics.NewInt(p.received[t])).
AddMetric("latency", metrics.NewFloat(p.latency[t].Seconds()/p.opts.LatencyUnit.Seconds())).
AddLabel("ptype", "ping").
AddLabel("probe", p.name).
AddLabel("dst", t)
dataChan <- em.Clone()
p.l.Info(em.String())
}
}
}
For dataChan <- em.Clone(), is this line of code redundant? The operation of the Clone function is to apply for a new memory, for the operation of the memory.
Tried the example on cloudprober.org calling google.com but it failed as in my network I can only make external calls via network http proxy settings but the system proxy settings are ignored and also there is no way to specify proxy url and port in the probe configuration.
This issue is to track the feature proposed in the PR:
#108
That PR is quite out of sync now and as the author has not responded on the PR for a while now, capturing the feature request here and closing the PR.
Currently, I am auditing using cloudprober with prometheus and postgres remote endpoint. It would simplify things drastically to be able to write to postgres directly from cloudprober. I would be happy to contribute this if it's something that could be in cloudprober.
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