relabel_config
重新标记是一个功能强大的工具，可以在目标的标签集被抓取之前重写它，每个采集配置可以配置多个重写标签设置，并按照配置的顺序来应用于每个目标的标签集。
目标重新标签之后，以__开头的标签将从标签集中删除的。
如果使用只需要临时的存储临时标签值的，可以使用_tmp作为前缀标识。
relabel的action类型
- replace: 对标签和标签值进行替换。
- keep: 满足特定条件的实例进行采集，其他的不采集。
- drop： 满足特定条件的实例不采集，其他的采集。
- hashmod： 这个我也没看懂啥意思，囧。
- labelmap： 这个我也没看懂啥意思，囧。
- labeldrop： 对抓取的实例特定标签进行删除。
- labelkeep： 对抓取的实例特定标签进行保留，其他标签删除。
常用action的测试
在测试前，同步下配置文件如下。
scrape_configs:
# The job name is added as a label `job=<job_name>` to any timeseries scraped from this config. - job_name: 'prometheus' # metrics_path defaults to '/metrics' # scheme defaults to 'http'. static_configs: - targets: ['localhost:9090'] - job_name: "node" file_sd_configs: - refresh_interval: 1m files: - "/usr/local/prometheus/prometheus/conf/node*.yml"
[root@node00 prometheus]# cat conf/node-dis.yml
- targets:
- "192.168.100.10:20001"
labels:
__hostname__: node00
__businees_line__: "line_a"
__region_id__: "cn-beijing"
__availability_zone__: "a"
- targets:
- "192.168.100.11:20001"
labels:
__hostname__: node01
__businees_line__: "line_a"
__region_id__: "cn-beijing"
__availability_zone__: "a"
- targets:
- "192.168.100.12:20001"
labels:
__hostname__: node02
__businees_line__: "line_c"
__region_id__: "cn-beijing"
__availability_zone__: "b"
此时如果查看target信息，如下图。
因为我们的label都是以__开头的，目标重新标签之后，以__开头的标签将从标签集中删除的。
一个简单的relabel设置
将labels中的__hostname__替换为node_name。
scrape_configs:
# The job name is added as a label `job=<job_name>` to any timeseries scraped from this config. - job_name: 'prometheus' # metrics_path defaults to '/metrics' # scheme defaults to 'http'. static_configs: - targets: ['localhost:9090'] - job_name: "node" file_sd_configs: - refresh_interval: 1m files: - "/usr/local/prometheus/prometheus/conf/node*.yml" relabel_configs: - source_labels: - "__hostname__" regex: "(.*)" target_label: "nodename" action: replace replacement: "$1"
重启服务查看target信息如下图：
说下上面的配置： source_labels指定我们我们需要处理的源标签， target_labels指定了我们要replace后的标签名字， action指定relabel动作，这里使用replace替换动作。 regex去匹配源标签（__hostname__）的值，"(.*)"代表__hostname__这个标签是什么值都匹配的，然后replacement指定的替换后的标签（target_label）对应的数值。采用正则引用方式获取的。
这里修改下上面的正则表达式为 ‘’regex: "(node00)"'的时候可以看到如下图。
keep
修改配置文件
scrape_configs:
# The job name is added as a label `job=<job_name>` to any timeseries scraped from this config. - job_name: 'prometheus' # metrics_path defaults to '/metrics' # scheme defaults to 'http'. static_configs: - targets: ['localhost:9090'] - job_name: "node" file_sd_configs: - refresh_interval: 1m files: - "/usr/local/prometheus/prometheus/conf/node*.yml"
target如下图
修改配置文件如下
scrape_configs:
# The job name is added as a label `job=<job_name>` to any timeseries scraped from this config. - job_name: 'prometheus' # metrics_path defaults to '/metrics' # scheme defaults to 'http'. static_configs: - targets: ['localhost:9090'] - job_name: "node" file_sd_configs: - refresh_interval: 1m files: - "/usr/local/prometheus/prometheus/conf/node*.yml" relabel_configs: - source_labels: - "__hostname__" regex: "node00" action: keep
target如下图
action为keep，只要source_labels的值匹配regex（node00）的实例才能会被采集。 其他的实例不会被采集。
drop
在上面的基础上，修改action为drop。
target如下图
action为drop，其实和keep是相似的， 不过是相反的， 只要source_labels的值匹配regex（node00）的实例不会被采集。 其他的实例会被采集。
replace
我们的基础信息里面有__region_id__和__availability_zone__，但是我想融合2个字段在一起，可以通过replace来实现。
修改配置如下
scrape_configs:
# The job name is added as a label `job=<job_name>` to any timeseries scraped from this config. - job_name: 'prometheus' # metrics_path defaults to '/metrics' # scheme defaults to 'http'. static_configs: - targets: ['localhost:9090'] - job_name: "node" file_sd_configs: - refresh_interval: 1m files: - "/usr/local/prometheus/prometheus/conf/node*.yml" relabel_configs: - source_labels: - "__region_id__" - "__availability_zone__" separator: "-" regex: "(.*)" target_label: "region_zone" action: replace replacement: "$1"
target如下图：
labelkeep
配置文件如下
scrape_configs:
# The job name is added as a label `job=<job_name>` to any timeseries scraped from this config. - job_name: 'prometheus' # metrics_path defaults to '/metrics' # scheme defaults to 'http'. static_configs: - targets: ['localhost:9090'] - job_name: "node" file_sd_configs: - refresh_interval: 1m files: - "/usr/local/prometheus/prometheus/conf/node*.yml" relabel_configs: - source_labels: - "__hostname__" regex: "(.*)" target_label: "nodename" action: replace replacement: "$1" - source_labels: - "__businees_line__" regex: "(.*)" target_label: "businees_line" action: replace replacement: "$1" - source_labels: - "__datacenter__" regex: "(.*)" target_label: "datacenter" action: replace replacement: "$1"
target如下图
修改配置文件如下
scrape_configs:
# The job name is added as a label `job=<job_name>` to any timeseries scraped from this config. - job_name: 'prometheus' # metrics_path defaults to '/metrics' # scheme defaults to 'http'. static_configs: - targets: ['localhost:9090'] - job_name: "node" file_sd_configs: - refresh_interval: 1m files: - "/usr/local/prometheus/prometheus/conf/node*.yml" relabel_configs: - source_labels: - "__hostname__" regex: "(.*)" target_label: "nodename" action: replace replacement: "$1" - source_labels: - "__businees_line__" regex: "(.*)" target_label: "businees_line" action: replace replacement: "$1" - source_labels: - "__datacenter__" regex: "(.*)" target_label: "datacenter" action: replace replacement: "$1" - regex: "(nodename|datacenter)" action: labeldrop
target如下图
