云原生日志收集方案Loki

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Hi,很高兴能够在掘金开发者的平台上为大家带来一套轻量级的kubernetes日志收集方案的相关介绍。我自己也在生产环境中使用过这套方案,令我意想不到的时它占用的kubernetes的资源相比与ELK这套方案真的是小巫见大巫。那接下来就跟随这篇文章开始学习它吧……

为什么要使用Loki

这篇文章着重介绍了grafana公司开发的loki日志收集应用。Loki是一个轻量级的日志收集、分析的应用,采用的是promtail的方式来获取日志内容并送到loki里面进行存储,最终在grafana的datasource里面添加数据源进行日志的展示、查询。

loki的持久化存储支持azuregcss3swiftlocal这5中类型,其中常用的是s3local。另外,它还支持很多种日志搜集类型,像最常用的logstashfluentbit也在官方支持的列表中。

那它有哪些优点呢?

  • 支持的客户端,如Promtail,Fluentbit,Fluentd,Vector,Logstash和Grafana Agent
  • 首选代理Promtail,可以多来源提取日志,包括本地日志文件,systemd,Windows事件日志,Docker日志记录驱动程序等
  • 没有日志格式要求,包括JSON,XML,CSV,logfmt,非结构化文本
  • 使用与查询指标相同的语法查询日志
  • 日志查询时允许动态筛选和转换日志行
  • 可以轻松地计算日志中的需要的指标
  • 引入时的最小索引意味着您可以在查询时动态地对日志进行切片和切块,以便在出现新问题时回答它们
  • 云原生支持,使用Prometheus形式抓取数据

各日志收集组件简单对比

名称安装的组件优点
ELK/EFKelasticsearch、logstash、kibana、filebeat、kafka/redis支持自定义grok正则解析复杂日志内容;dashboard支持丰富的可视化展示
Lokigrafana、loki、promtail占用资源小;grafana原生支持;查询速度快;

Loki工作方式解惑

日志解析格式

image.png

从上面的图中我们可以看到,它在解析日志的时候是以index为主的,index包括时间戳和pod的部分label(其他label为filename、containers等),其余的是日志内容。具体查询效果如下: image.png

image.png {app="loki",namespace="kube-public"}为索引

日志搜集架构模式

image.png 在使用过程中,官方推荐使用promtail做为agent以DaemonSet方式部署在kubernetes的worker节点上搜集日志。另外也可以用上面提到的其他日志收集工具来收取,这篇文章在结尾处会附上其他工具的配置方式。

Loki部署模式都有哪些呢

Loki由许多组件微服务构建而成,微服务组件有5个。在这5个里面添加缓存用来把数据放起来加快查询。数据放在共享存储里面配置memberlist_config部分并在实例之间共享状态,将Loki进行无限横向扩展。在配置完memberlist_config部分后采用轮询的方式查找数据。为了使用方便官方把所有的微服务编译成一个二进制,可以通过命令行参数-target控制,支持allreadwrite,我们在部署时根据日志量的大小可以指定不同模式

all(读写模式)

服务启动后,我们做的数据查询、数据写入都是来自这一个节点。请看下面的这个图解: image.png

read/write(读写分离模式)

在读写分离模式下运行时fronted-query查询会将流量转发到read节点上。读节点上保留了querierrulerfronted,写节点上保留了distributoringester

image.png

微服务模式运行

微服务模式运行下,通过不同的配置参数启动为不同的角色,每一个进程都引用它的目标角色服务。

image.png

组件名称功能
分发器/调度器(distributor)验证数据合规;数据排序;hash一致性;QPS限制;转发;数据副本保证不丢失
收集器(ingester)时间戳排序;文件系统支持;WAL预写;
查询前端(query-frontend)提供页面操作,向后端存储发出数据查询;查询队列(query-queueing)能够防止大数据量查询时触发OOM;查询分割(query-split)可以分割大批量查询最后进行数据聚合
查询器Querier使用logql语言在后端存储中查询日志
缓存将查询到的日志缓存起来共后续使用,如果数据不完整重新查询缺失的数据

大显身手之服务端部署

上面我们讲了那么多关于loki的介绍和它的工作模式,你也一定期待它是怎么部署的吧?!该怎么部署、部署在哪里、部署后怎么使用等等问题都会出现在你的脑海里。在部署之前你需要准备好一个k8s集群才行哦。那好,接下来耐着性子往下看……

应用镜像
lokigrafana/loki:2.5.0
promtailgrafana/promtail:2.5.0

AllInOne部署模式

① k8s部署

我们从github上下载的程序是没有配置文件的,需要提前将文件准备一份。这里提供了一份完整的allInOne配置文件,部分内容进行了优化。

配置文件内容如下所示

auth_enabled: false
target: all
ballast_bytes: 20480
server:
  grpc_listen_port: 9095
  http_listen_port: 3100
  graceful_shutdown_timeout: 20s
  grpc_listen_address: "0.0.0.0"
  grpc_listen_network: "tcp"
  grpc_server_max_concurrent_streams: 100
  grpc_server_max_recv_msg_size: 4194304
  grpc_server_max_send_msg_size: 4194304
  http_server_idle_timeout: 2m
  http_listen_address: "0.0.0.0"
  http_listen_network: "tcp"
  http_server_read_timeout: 30s
  http_server_write_timeout: 20s
  log_source_ips_enabled: true
  # http_path_prefix如果需要更改,在推送日志的时候前缀都需要加指定的内容
  # http_path_prefix: "/"
  register_instrumentation: true
  log_format: json
  log_level: info
distributor:
  ring:
    heartbeat_timeout: 3s
    kvstore:
      prefix: collectors/
      store: memberlist
      # 需要提前创建好consul集群
    #   consul:
    #     http_client_timeout: 20s
    #     consistent_reads: true
    #     host: 127.0.0.1:8500
    #     watch_burst_size: 2
    #     watch_rate_limit: 2
querier:
  engine:
    max_look_back_period: 20s 
    timeout: 3m0s 
  extra_query_delay: 100ms 
  max_concurrent: 10 
  multi_tenant_queries_enabled: true
  query_ingester_only: false
  query_ingesters_within: 3h0m0s
  query_store_only: false
  query_timeout: 5m0s
  tail_max_duration: 1h0s
query_scheduler:
  max_outstanding_requests_per_tenant: 2048
  grpc_client_config:
    max_recv_msg_size: 104857600
    max_send_msg_size: 16777216
    grpc_compression: gzip
    rate_limit: 0
    rate_limit_burst: 0
    backoff_on_ratelimits: false
    backoff_config:
      min_period: 50ms
      max_period: 15s
      max_retries: 5 
  use_scheduler_ring: true
  scheduler_ring:
    kvstore:
      store: memberlist
      prefix: "collectors/"
    heartbeat_period: 30s
    heartbeat_timeout: 1m0s
    # 默认第一个网卡的名称
    # instance_interface_names
    # instance_addr: 127.0.0.1
    # 默认server.grpc-listen-port
    instance_port: 9095
frontend:
  max_outstanding_per_tenant: 4096
  querier_forget_delay: 1h0s
  compress_responses: true
  log_queries_longer_than: 2m0s
  max_body_size: 104857600
  query_stats_enabled: true
  scheduler_dns_lookup_period: 10s 
  scheduler_worker_concurrency: 15
query_range:
  align_queries_with_step: true
  cache_results: true
  parallelise_shardable_queries: true
  max_retries: 3
  results_cache:
    cache:
      enable_fifocache: false
      default_validity: 30s 
      background:
        writeback_buffer: 10000
      redis:
        endpoint: 127.0.0.1:6379
        timeout: 1s
        expiration: 0s 
        db: 9
        pool_size: 128 
        password: 1521Qyx6^
        tls_enabled: false
        tls_insecure_skip_verify: true
        idle_timeout: 10s 
        max_connection_age: 8h
ruler:
  enable_api: true
  enable_sharding: true
  alertmanager_refresh_interval: 1m
  disable_rule_group_label: false
  evaluation_interval: 1m0s
  flush_period: 3m0s
  for_grace_period: 20m0s
  for_outage_tolerance: 1h0s
  notification_queue_capacity: 10000
  notification_timeout: 4s
  poll_interval: 10m0s
  query_stats_enabled: true
  remote_write:
    config_refresh_period: 10s
    enabled: false
  resend_delay: 2m0s
  rule_path: /rulers
  search_pending_for: 5m0s
  storage:
    local:
      directory: /data/loki/rulers
    type: configdb
  sharding_strategy: default
  wal_cleaner:
    period:  240h
    min_age: 12h0m0s
  wal:
    dir: /data/loki/ruler_wal
    max_age: 4h0m0s
    min_age: 5m0s
    truncate_frequency: 1h0m0s
  ring:
    kvstore:
      store: memberlist
      prefix: "collectors/"
    heartbeat_period: 5s
    heartbeat_timeout: 1m0s
    # instance_addr: "127.0.0.1"
    # instance_id: "miyamoto.en0"
    # instance_interface_names: ["en0","lo0"]
    instance_port: 9500
    num_tokens: 100
ingester_client:
  pool_config:
    health_check_ingesters: false
    client_cleanup_period: 10s 
    remote_timeout: 3s
  remote_timeout: 5s 
ingester:
  autoforget_unhealthy: true
  chunk_encoding: gzip
  chunk_target_size: 1572864
  max_transfer_retries: 0
  sync_min_utilization: 3.5
  sync_period: 20s
  flush_check_period: 30s 
  flush_op_timeout: 10m0s
  chunk_retain_period: 1m30s
  chunk_block_size: 262144
  chunk_idle_period: 1h0s
  max_returned_stream_errors: 20
  concurrent_flushes: 3
  index_shards: 32
  max_chunk_age: 2h0m0s
  query_store_max_look_back_period: 3h30m30s
  wal:
    enabled: true
    dir: /data/loki/wal 
    flush_on_shutdown: true
    checkpoint_duration: 15m
    replay_memory_ceiling: 2GB
  lifecycler:
    ring:
      kvstore:
        store: memberlist
        prefix: "collectors/"
      heartbeat_timeout: 30s 
      replication_factor: 1
    num_tokens: 128
    heartbeat_period: 5s 
    join_after: 5s 
    observe_period: 1m0s
    # interface_names: ["en0","lo0"]
    final_sleep: 10s 
    min_ready_duration: 15s
storage_config:
  boltdb:
    directory: /data/loki/boltdb 
  boltdb_shipper:
    active_index_directory: /data/loki/active_index
    build_per_tenant_index: true
    cache_location: /data/loki/cache 
    cache_ttl: 48h
    resync_interval: 5m
    query_ready_num_days: 5
    index_gateway_client:
      grpc_client_config:
  filesystem:
    directory: /data/loki/chunks
chunk_store_config:
  chunk_cache_config:
    enable_fifocache: true
    default_validity: 30s
    background:
      writeback_buffer: 10000
    redis:
      endpoint: 192.168.3.56:6379
      timeout: 1s
      expiration: 0s 
      db: 8 
      pool_size: 128 
      password: 1521Qyx6^
      tls_enabled: false
      tls_insecure_skip_verify: true
      idle_timeout: 10s 
      max_connection_age: 8h
    fifocache:
      ttl: 1h
      validity: 30m0s
      max_size_items: 2000
      max_size_bytes: 500MB
  write_dedupe_cache_config:
    enable_fifocache: true
    default_validity: 30s 
    background:
      writeback_buffer: 10000
    redis:
      endpoint: 127.0.0.1:6379
      timeout: 1s
      expiration: 0s 
      db: 7
      pool_size: 128 
      password: 1521Qyx6^
      tls_enabled: false
      tls_insecure_skip_verify: true
      idle_timeout: 10s 
      max_connection_age: 8h
    fifocache:
      ttl: 1h
      validity: 30m0s
      max_size_items: 2000
      max_size_bytes: 500MB
  cache_lookups_older_than: 10s 
# 压缩碎片索引
compactor:
  shared_store: filesystem
  shared_store_key_prefix: index/
  working_directory: /data/loki/compactor
  compaction_interval: 10m0s
  retention_enabled: true
  retention_delete_delay: 2h0m0s
  retention_delete_worker_count: 150
  delete_request_cancel_period: 24h0m0s
  max_compaction_parallelism: 2
  # compactor_ring:
frontend_worker:
  match_max_concurrent: true
  parallelism: 10
  dns_lookup_duration: 5s 
# runtime_config 这里没有配置任何信息
# runtime_config:
common:
  storage:
    filesystem:
      chunks_directory: /data/loki/chunks
      fules_directory: /data/loki/rulers
  replication_factor: 3
  persist_tokens: false
  # instance_interface_names: ["en0","eth0","ens33"]
analytics:
  reporting_enabled: false
limits_config:
  ingestion_rate_strategy: global
  ingestion_rate_mb: 100
  ingestion_burst_size_mb: 18
  max_label_name_length: 2096
  max_label_value_length: 2048
  max_label_names_per_series: 60
  enforce_metric_name: true
  max_entries_limit_per_query: 5000
  reject_old_samples: true
  reject_old_samples_max_age: 168h
  creation_grace_period: 20m0s
  max_global_streams_per_user: 5000
  unordered_writes: true
  max_chunks_per_query: 200000
  max_query_length: 721h
  max_query_parallelism: 64 
  max_query_series: 700
  cardinality_limit: 100000
  max_streams_matchers_per_query: 1000 
  max_concurrent_tail_requests: 10 
  ruler_evaluation_delay_duration: 3s 
  ruler_max_rules_per_rule_group: 0
  ruler_max_rule_groups_per_tenant: 0
  retention_period: 700h
  per_tenant_override_period: 20s 
  max_cache_freshness_per_query: 2m0s
  max_queriers_per_tenant: 0
  per_stream_rate_limit: 6MB
  per_stream_rate_limit_burst: 50MB
  max_query_lookback: 0
  ruler_remote_write_disabled: false
  min_sharding_lookback: 0s
  split_queries_by_interval: 10m0s
  max_line_size: 30mb
  max_line_size_truncate: false
  max_streams_per_user: 0

# memberlist_conig模块配置gossip用于在分发服务器、摄取器和查询器之间发现和连接。
# 所有三个组件的配置都是唯一的,以确保单个共享环。
# 至少定义了1个join_members配置后,将自动为分发服务器、摄取器和ring 配置memberlist类型的kvstore
memberlist:
  randomize_node_name: true
  stream_timeout: 5s 
  retransmit_factor: 4
  join_members:
  - 'loki-memberlist'
  abort_if_cluster_join_fails: true
  advertise_addr: 0.0.0.0
  advertise_port: 7946
  bind_addr: ["0.0.0.0"]
  bind_port: 7946
  compression_enabled: true
  dead_node_reclaim_time: 30s
  gossip_interval: 100ms
  gossip_nodes: 3
  gossip_to_dead_nodes_time: 3
  # join:
  leave_timeout: 15s
  left_ingesters_timeout: 3m0s 
  max_join_backoff: 1m0s
  max_join_retries: 5
  message_history_buffer_bytes: 4096
  min_join_backoff: 2s
  # node_name: miyamoto
  packet_dial_timeout: 5s
  packet_write_timeout: 5s 
  pull_push_interval: 100ms
  rejoin_interval: 10s
  tls_enabled: false
  tls_insecure_skip_verify: true
schema_config:
  configs:
  - from: "2020-10-24"
    index:
      period: 24h
      prefix: index_
    object_store: filesystem
    schema: v11
    store: boltdb-shipper
    chunks:
      period: 168h
    row_shards: 32
table_manager:
  retention_deletes_enabled: false
  retention_period: 0s
  throughput_updates_disabled: false
  poll_interval: 3m0s
  creation_grace_period: 20m
  index_tables_provisioning:
    provisioned_write_throughput: 1000
    provisioned_read_throughput: 500
    inactive_write_throughput: 4
    inactive_read_throughput: 300
    inactive_write_scale_lastn: 50 
    enable_inactive_throughput_on_demand_mode: true
    enable_ondemand_throughput_mode: true
    inactive_read_scale_lastn: 10 
    write_scale:
      enabled: true
      target: 80
      # role_arn:
      out_cooldown: 1800
      min_capacity: 3000
      max_capacity: 6000
      in_cooldown: 1800
    inactive_write_scale:
      enabled: true
      target: 80
      out_cooldown: 1800
      min_capacity: 3000
      max_capacity: 6000
      in_cooldown: 1800
    read_scale:
      enabled: true
      target: 80
      out_cooldown: 1800
      min_capacity: 3000
      max_capacity: 6000
      in_cooldown: 1800
    inactive_read_scale:
      enabled: true
      target: 80
      out_cooldown: 1800
      min_capacity: 3000
      max_capacity: 6000
      in_cooldown: 1800
  chunk_tables_provisioning:
    enable_inactive_throughput_on_demand_mode: true
    enable_ondemand_throughput_mode: true
    provisioned_write_throughput: 1000
    provisioned_read_throughput: 300
    inactive_write_throughput: 1
    inactive_write_scale_lastn: 50
    inactive_read_throughput: 300
    inactive_read_scale_lastn: 10
    write_scale:
      enabled: true
      target: 80
      out_cooldown: 1800
      min_capacity: 3000
      max_capacity: 6000
      in_cooldown: 1800
    inactive_write_scale:
      enabled: true
      target: 80
      out_cooldown: 1800
      min_capacity: 3000
      max_capacity: 6000
      in_cooldown: 1800
    read_scale:
      enabled: true
      target: 80
      out_cooldown: 1800
      min_capacity: 3000
      max_capacity: 6000
      in_cooldown: 1800
    inactive_read_scale:
      enabled: true
      target: 80
      out_cooldown: 1800
      min_capacity: 3000
      max_capacity: 6000
      in_cooldown: 1800
tracing:
  enabled: true

注意:

  • ingester.lifecycler.ring.replication_factor的值在单实例的情况下为1
  • ingester.lifecycler.min_ready_duration的值为15s,在启动后默认会显示15秒将状态变为ready

image.png

  • memberlist.node_name的值可以不用设置,默认是当前主机的名称
  • memberlist.join_members是一个列表,在有多个实例的情况下需要添加各个节点的主机名/IP地址。在k8s里面可以设置成一个service绑定到StatefulSets
  • query_range.results_cache.cache.enable_fifocache建议设置为false,我这里设置成了true
  • instance_interface_names是一个列表,默认的为["en0","eth0"],可以根据需要设置对应的网卡名称,一般不需要进行特殊设置。

创建configmap

说明:将上面的内容写入到一个文件——>loki-all.yaml,把它作为一个configmap写入k8s集群。可以使用如下命令创建:

kubectl create configmap --from-file ./loki-all.yaml loki-all

可以通过命令查看到已经创建好的configmap,具体操作详见下图 image.png

创建持久化存储

在k8s里面我们的数据是需要进行持久化的。Loki收集起来的日志信息对于业务来说是至关重要的,因此需要在容器重启的时候日志能够保留下来。那么就需要用到pvpvc,后端存储可以使用nfsglusterfshostPathazureDiskcephfs等20种支持类型,这里因为没有对应的环境就采用了hostPath方式。

apiVersion: v1
kind: PersistentVolume
metadata:
  name: loki
  namespace: default
spec:
  hostPath:
    path: /glusterfs/loki
    type: DirectoryOrCreate
  capacity:
    storage: 1Gi
  accessModes:
    - ReadWriteMany
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: loki
  namespace: default
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Gi
  volumeName: loki

创建应用

准备好k8s的StatefulSet部署文件后就可以直接在集群里面创建应用了。

apiVersion: apps/v1
kind: StatefulSet
metadata:
  labels:
    app: loki
  name: loki
  namespace: default
spec:
  podManagementPolicy: OrderedReady
  replicas: 1
  selector:
    matchLabels:
      app: loki
  template:
    metadata:
      annotations:
        prometheus.io/port: http-metrics
        prometheus.io/scrape: "true"
      labels:
        app: loki
    spec:
      containers:
      - args:
        - -config.file=/etc/loki/loki-all.yaml
        image: grafana/loki:2.5.0
        imagePullPolicy: IfNotPresent
        livenessProbe:
          failureThreshold: 3
          httpGet:
            path: /ready
            port: http-metrics
            scheme: HTTP
          initialDelaySeconds: 45
          periodSeconds: 10
          successThreshold: 1
          timeoutSeconds: 1
        name: loki
        ports:
        - containerPort: 3100
          name: http-metrics
          protocol: TCP
        - containerPort: 9095
          name: grpc
          protocol: TCP
        - containerPort: 7946
          name: memberlist-port
          protocol: TCP
        readinessProbe:
          failureThreshold: 3
          httpGet:
            path: /ready
            port: http-metrics
            scheme: HTTP
          initialDelaySeconds: 45
          periodSeconds: 10
          successThreshold: 1
          timeoutSeconds: 1
        resources:
          requests:
            cpu: 500m
            memory: 500Mi
          limits:
            cpu: 500m
            memory: 500Mi
        securityContext:
          readOnlyRootFilesystem: true
        volumeMounts:
        - mountPath: /etc/loki
          name: config
        - mountPath: /data
          name: storage
      restartPolicy: Always
      securityContext:
        fsGroup: 10001
        runAsGroup: 10001
        runAsNonRoot: true
        runAsUser: 10001
      serviceAccount: loki
      serviceAccountName: loki
      volumes:
      - emptyDir: {}
        name: tmp
      - name: config
        configMap:
          name: loki
      - persistentVolumeClaim:
          claimName: loki
        name: storage
---
kind: Service
apiVersion: v1
metadata:
  name: loki-memberlist
  namespace: default
spec:
  ports:
    - name: loki-memberlist
      protocol: TCP
      port: 7946
      targetPort: 7946
  selector:
    kubepi.org/name: loki
---
kind: Service
apiVersion: v1
metadata:
  name: loki
  namespace: default
spec:
  ports:
    - name: loki
      protocol: TCP
      port: 3100
      targetPort: 3100
  selector:
    kubepi.org/name: loki

在上面的配置文件中我添加了一些pod级别的安全策略,这些安全策略还有集群级别的PodSecurityPolicy,防止因为漏洞的原因造成集群的整个崩溃,关于集群级别的psp,可以详见官方文档

验证部署结果

image.png 当看到上面的Running状态时可以通过API的方式看一下分发器是不是正常工作,当显示Active时正常才会正常分发日志流到收集器(ingester)

image.png

② 裸机部署

loki放到系统的/bin/目录下,准备grafana-loki.service控制文件重载系统服务列表

[Unit]
Description=Grafana Loki Log Ingester
Documentation=https://grafana.com/logs/
After=network-online.target

[Service]
ExecStart=/bin/loki --config.file /etc/loki/loki-all.yaml
ExecReload=/bin/kill -s HUP $MAINPID
ExecStop=/bin/kill -s TERM $MAINPID

[Install]
WantedBy=multi-user.target

重载系统列表命令,可以直接系统自动管理服务:

systemctl daemon-reload
# 启动服务
systemctl start grafana-loki
# 停止服务
systemctl stop grafana-loki
# 重载应用
systemctl reload grafana-loki

大显身手之Promtail部署

部署客户端收集日志时也需要创建一个配置文件,按照上面创建服务端的步骤创建。不同的是需要把日志内容push到服务端

① k8s部署

创建配置文件

server:
  log_level: info
  http_listen_port: 3101
clients:
  - url: http://loki:3100/loki/api/v1/push
positions:
  filename: /run/promtail/positions.yaml
scrape_configs:
  - job_name: kubernetes-pods
    pipeline_stages:
      - cri: {}
    kubernetes_sd_configs:
      - role: pod
    relabel_configs:
      - source_labels:
          - __meta_kubernetes_pod_controller_name
        regex: ([0-9a-z-.]+?)(-[0-9a-f]{8,10})?
        action: replace
        target_label: __tmp_controller_name
      - source_labels:
          - __meta_kubernetes_pod_label_app_kubernetes_io_name
          - __meta_kubernetes_pod_label_app
          - __tmp_controller_name
          - __meta_kubernetes_pod_name
        regex: ^;*([^;]+)(;.*)?$
        action: replace
        target_label: app
      - source_labels:
          - __meta_kubernetes_pod_label_app_kubernetes_io_instance
          - __meta_kubernetes_pod_label_release
        regex: ^;*([^;]+)(;.*)?$
        action: replace
        target_label: instance
      - source_labels:
          - __meta_kubernetes_pod_label_app_kubernetes_io_component
          - __meta_kubernetes_pod_label_component
        regex: ^;*([^;]+)(;.*)?$
        action: replace
        target_label: component
      - action: replace
        source_labels:
        - __meta_kubernetes_pod_node_name
        target_label: node_name
      - action: replace
        source_labels:
        - __meta_kubernetes_namespace
        target_label: namespace
      - action: replace
        replacement: $1
        separator: /
        source_labels:
        - namespace
        - app
        target_label: job
      - action: replace
        source_labels:
        - __meta_kubernetes_pod_name
        target_label: pod
      - action: replace
        source_labels:
        - __meta_kubernetes_pod_container_name
        target_label: container
      - action: replace
        replacement: /var/log/pods/*$1/*.log
        separator: /
        source_labels:
        - __meta_kubernetes_pod_uid
        - __meta_kubernetes_pod_container_name
        target_label: __path__
      - action: replace
        regex: true/(.*)
        replacement: /var/log/pods/*$1/*.log
        separator: /
        source_labels:
        - __meta_kubernetes_pod_annotationpresent_kubernetes_io_config_hash
        - __meta_kubernetes_pod_annotation_kubernetes_io_config_hash
        - __meta_kubernetes_pod_container_name
        target_label: __path__

用上面的内容创建一个configMap,方法同上

创建DaemonSet文件

Promtail是一个无状态应用不需要进行持久化存储只需要部署到集群里面就可以了,还是同样的准备DaemonSets创建文件。

kind: DaemonSet
apiVersion: apps/v1
metadata:
  name: promtail
  namespace: default
  labels:
    app.kubernetes.io/instance: promtail
    app.kubernetes.io/name: promtail
    app.kubernetes.io/version: 2.5.0
spec:
  selector:
    matchLabels:
      app.kubernetes.io/instance: promtail
      app.kubernetes.io/name: promtail
  template:
    metadata:
      labels:
        app.kubernetes.io/instance: promtail
        app.kubernetes.io/name: promtail
    spec:
      volumes:
        - name: config
          configMap:
            name: promtail
        - name: run
          hostPath:
            path: /run/promtail
        - name: containers
          hostPath:
            path: /var/lib/docker/containers
        - name: pods
          hostPath:
            path: /var/log/pods
      containers:
        - name: promtail
          image: docker.io/grafana/promtail:2.3.0
          args:
            - '-config.file=/etc/promtail/promtail.yaml'
          ports:
            - name: http-metrics
              containerPort: 3101
              protocol: TCP
          env:
            - name: HOSTNAME
              valueFrom:
                fieldRef:
                  apiVersion: v1
                  fieldPath: spec.nodeName
          volumeMounts:
            - name: config
              mountPath: /etc/promtail
            - name: run
              mountPath: /run/promtail
            - name: containers
              readOnly: true
              mountPath: /var/lib/docker/containers
            - name: pods
              readOnly: true
              mountPath: /var/log/pods
          readinessProbe:
            httpGet:
              path: /ready
              port: http-metrics
              scheme: HTTP
            initialDelaySeconds: 10
            timeoutSeconds: 1
            periodSeconds: 10
            successThreshold: 1
            failureThreshold: 5
          imagePullPolicy: IfNotPresent
          securityContext:
            capabilities:
              drop:
                - ALL
            readOnlyRootFilesystem: false
            allowPrivilegeEscalation: false
      restartPolicy: Always
      serviceAccountName: promtail
      serviceAccount: promtail
      tolerations:
        - key: node-role.kubernetes.io/master
          operator: Exists
          effect: NoSchedule
        - key: node-role.kubernetes.io/control-plane
          operator: Exists
          effect: NoSchedule

创建promtail应用

kubectl apply -f promtail.yaml

使用上面这个命令创建后就可以看到服务已经创建好了。接下来就是在Grafana里面添加DataSource查看数据了。 image.png

② 裸机部署

如果是裸机部署的情况下,需要对上面的配置文件做一下稍微的改动,更改clients得地址就可以,文件存放到/etc/loki/下,例如改成:

clients:
  - url: http://ipaddress:port/loki/api/v1/push

添加系统开机启动配置,service配置文件存放位置/usr/lib/systemd/system/loki-promtail.service内容如下

[Unit]
Description=Grafana Loki Log Ingester
Documentation=https://grafana.com/logs/
After=network-online.target

[Service]
ExecStart=/bin/promtail --config.file /etc/loki/loki-promtail.yaml
ExecReload=/bin/kill -s HUP $MAINPID
ExecStop=/bin/kill -s TERM $MAINPID

[Install]
WantedBy=multi-user.target

启动方式同上面服务端部署内容

Loki in DataSource

添加数据源

具体步骤: Grafana->Setting->DataSources->AddDataSource->Loki

注意点: http的URL地址,应用、服务部署在哪个namespace下,就需要指定它的FQDN地址,它的格式是ServiceName.namespace。如果默认在default下、创建的端口号是3100,就需要填写为http://loki:3100,这里为什么不写IP地址而写成服务的名字,是因为在k8s集群里面有个dns服务器会自动解析这个地址。 添加数据源.png

查找日志信息

页面展示.png

其他客户端配置

Logstash作为日志收集客户端

安装插件

在启动Logstash后我们需要安装一个插件,可以通过这个命令安装loki的输出插件,安装完成之后可以在logstash的output中添加信息。

bin/logstash-plugin install logstash-output-loki

添加配置进行测试

完整的logstash配置信息,可以参考官网给出的内容LogstashConfigFile

output {
  loki {
    [url => "" | default = none | required=true]
    [tenant_id => string | default = nil | required=false]
    [message_field => string | default = "message" | required=false]
    [include_fields => array | default = [] | required=false]
    [batch_wait => number | default = 1(s) | required=false]
    [batch_size => number | default = 102400(bytes) | required=false]
    [min_delay => number | default = 1(s) | required=false]
    [max_delay => number | default = 300(s) | required=false]
    [retries => number | default = 10 | required=false]
    [username => string | default = nil | required=false]
    [password => secret | default = nil | required=false]
    [cert => path | default = nil | required=false]
    [key => path | default = nil| required=false]
    [ca_cert => path | default = nil | required=false]
    [insecure_skip_verify => boolean | default = false | required=false]
  }
}

或者采用logstash的http输出模块,配置如下:

output {
    http {
        format => "json"
        http_method => "post"
        content_type => "application/json"
        connect_timeout => 10
        url => "http://loki:3100/loki/api/v1/push"
        message => '"message":"%{message}"}'
    }
}

Helm安装

如果你想简便安装的话,可以采用helm来安装。helm将所有的安装步骤都进行了封装,简化了安装步骤。对于想详细了解k8s的人来说,helm不太适合。因为它封装后自动执行,k8s管理员不知道各组件之间是如何依赖的,可能会造成误区。 废话不多说,下面开始helm安装

添加repo源

helm repo add grafana https://grafana.github.io/helm-charts

更新源

helm repo update

部署

默认配置

helm upgrade --install loki grafana/loki-simple-scalable

自定义namespace

helm upgrade --install loki --namespace=loki grafana/loki-simple-scalable

自定义配置信息

helm upgrade --install loki grafana/loki-simple-scalable --set "key1=val1,key2=val2,..."

故障解决方案

502 BadGateWay

  • loki的地址填写不正确
    • 在k8s里面,地址填写错误造成了502。检查一下loki的地址是否是以下内容:
      • http://LokiServiceName
      • http://LokiServiceName.namespace
      • http://LokiServiceName.namespace:ServicePort
    • grafana和loki在不同的节点上,检查一下节点间网络通信状态、防火墙策略

Ingester not ready: instance xx:9095 in state JOINING

  • 耐心等待一会,因为是allInOne模式程序启动需要一定的时间。

too many unhealthy instances in the ring

  • ingester.lifecycler.replication_factor改为1,是因为这个设置不正确造成的。这个在启动的时候会设置为多个复制源,但当前只部署了一个所以在查看label的时候提示这个

Data source connected, but no labels received. Verify that Loki and Promtail is configured properly

  • promtail无法将收集到的日志发送给loki,许可检查一下promtail的输出是不是正常
  • promtail在loki还没有准备就绪的时候把日志发送过来了,但loki没有接收到。如果需要重新接收日志,需要删除positions.yaml文件,具体路径可以用find查找一下位置
  • promtail忽略了目标日志文件或者配置文件错误造成的无法正常启动
  • promtail无法在指定的位置发现日志文件 配置文件参考1