You need to define different modules with the different sets of parameters
you require, e.g.
modules:
http_2xx:
prober: http
timeout: 10s
http:
follow_redirects: false
headers:
User-Agent: "BlackBox-Exporter/EO"
preferred_ip_protocol: "ip4"
http_2xx_ie:
prober: http
timeout: 10s
http:
follow_redirects: false
headers:
* User-Agent: "InternetExplorer 1.0"*
preferred_ip_protocol: "ip4"
Then you need to set __param_module to point to that (named) module. The
config I provided before copies the "module" label (set in the targets
list) to the "__param_module" label.
The reason you should do this, rather than just set "__param_module"
directly in the targets list, is because if you scrape the same target with
multiple modules, you need the timeseries to be distinct; and the
timeseries is defined by its set of labels. Target labels which start with
double-underscore are used to control scraping but are removed from the
final label set.
BTW, I recommend using file_sd_configs rather than static_configs. The
format is exactly the same (a list of targets+labels), but you can change
the targets file without having to HUP prometheus.
On Wednesday, 11 August 2021 at 00:04:29 UTC+1 Sebastian N. wrote:
> Hey Brian,
>
> thanks for the quick and detailed answer. It's really insightful so I'll
> be sure to adapt that to our needs. However, I'm still a bit lost how I can
> solve my requirement (maybe my approach is wrong or it's simply not
> possible).
> Given this blackbox-exporter module definition...
>
> modules:
> http_2xx:
> prober: http
> timeout: 10s
> http:
> follow_redirects: false
> headers:
> User-Agent: "BlackBox-Exporter/EO"
> preferred_ip_protocol: "ip4"
>
> and this Prometheus scraping config...
>
> prometheus_scrape_configs:
> scrape_configs:
> - job_name: 'blackbox-http'
> scrape_interval: 5m
> metrics_path: /probe
> params:
> module: [http_2xx]
> static_configs:
> - targets:
> - https://foo.dev.contoso.com/
> - https://foo.dev.contoso.com/cms/
> - https://foo.dev.contoso.com/dealer-portal/
> - https://bar.dev.contoso.com/
> - https://bar.dev.contoso.com/cms/
> - https://bar.dev.contoso.com/dealer-portal/
> labels:
> env: dev
> - targets:
> - https://foo.int.contoso.com/
> - https://foo.int.contoso.com/cms/
> - https://foo.int.contoso.com/dealer-portal/
> - https://bar.int.contoso.com/
> - https://bar.int.contoso.com/cms/
> - https://bar.int.contoso.com/dealer-portal/
> labels:
> env: int
> - targets:
> - https://foo.contoso.com/
> - https://foo.contoso.com/cms/
> - https://foo.contoso.com/dealer-portal/
> - https://bar.contoso.com/
> - https://bar.contoso.com/cms/
> - https://bar.contoso.com/dealer-portal/
> labels:
> env: prod
>
> relabel_configs:
> - source_labels: [__address__]
> target_label: __param_target
> - source_labels: [__param_target]
> target_label: instance
> - target_label: __address__
> replacement: blackbox-exporter:9115 # Docker service name
> - target_label: project
> replacement: contoso
>
> ...is there any way to override the module parameters on a per-target
> basis? E.g. change user agent, enable/disable certificate trust,
> enable/disable following redirects for a single target?
>
> Kind regards,
> Seb
>
>
> On Friday, August 6, 2021 at 1:32:29 PM UTC+2 Brian Candler wrote:
>
>> This should work:
>>
>> - job_name: blackbox
>> file_sd_configs:
>> - files:
>> - /etc/prometheus/blackbox.d/*.yml
>> metrics_path: /probe
>> relabel_configs:
>> - source_labels: [__address__]
>> target_label: __param_target
>> - source_labels: [module]
>> target_label: __param_module
>> - target_label: __address__
>> replacement: 127.0.0.1:9115 # Blackbox exporter
>>
>> That is, you set a label "module" in your targets file, and it gets
>> copied to __param_module. Your targets files
>> /etc/prometheus/blackbox.d/foo.yml look like this:
>>
>> - labels:
>> module: icmp
>> targets:
>> - 1.1.1.1
>> - 2.2.2.2
>> - labels:
>> module: dns
>> targets:
>> - 3.3.3.3
>> ... etc
>>
>> All your blackbox scrapes are done in a single job.
>>
>> The actual config I use is a little more complex than that:
>>
>> - job_name: blackbox
>> file_sd_configs:
>> - files:
>> - /etc/prometheus/blackbox.d/*.yml
>> metrics_path: /probe
>> relabel_configs:
>> - source_labels: [__address__]
>> regex: '([^/]+)' # name or address only
>> target_label: instance
>> - source_labels: [__address__]
>> regex: '([^/]+)' # name or address only
>> target_label: __param_target
>> - source_labels: [__address__]
>> regex: '(.+)/(.+)' # name/address
>> target_label: instance
>> replacement: '${1}'
>> - source_labels: [__address__]
>> regex: '(.+)/(.+)' # name/address
>> target_label: __param_target
>> replacement: '${2}'
>> - source_labels: [module]
>> target_label: __param_module
>> - target_label: __address__
>> replacement: 127.0.0.1:9115 # Blackbox exporter
>>
>> This lets me use target entries of the form
>> "<instance-label>/<address-or-hostname>", e.g.
>>
>> - labels:
>> module: icmp
>> targets:
>> - google-primary/8.8.8.8
>> - google-secondary/8.8.4.4
>>
>> so my metrics have meaningful instance labels
>> <https://www.robustperception.io/controlling-the-instance-label>.
>>
>> On Friday, 6 August 2021 at 10:17:06 UTC+1 Sebastian N. wrote:
>>
>>> Hey guys,
>>>
>>> In the following discussion
>>> <https://groups.google.com/g/prometheus-users/c/a0uePOVkG1c/m/4u0NwDN5AwAJ>
>>> about the blackbox exporter Julius Volz mentioned the following:
>>>
>>> The Blackbox targets to probe (like "https://google.com";) can come from
>>> file_sd (or any other SD), no problem. You still need a scrape config in
>>> the Prometheus config that actually scrapes the Blackbox exporter, but it
>>> can get targets to probe from file_sd. *You can even vary the Blackbox
>>> Exporter probe module to use for each target by setting a "__param_module"
>>> hidden label on each target to override any "module" HTTP param that is set
>>> in the scrape config itself.*
>>>
>>> During my research I have not found an example that shows me how I can
>>> override module parameters on a per-target basis. My use case is that I'd
>>> like to set a different user agent or toggle the follow_redirects flag for
>>> some hosts without having to create another scraping job for that.
>>>
>>
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