架構(gòu)

Logstash 工作原理

增量同步原理

流程

準備工作

1）源碼下載直接解壓安裝包，開箱即用

2）修改對內(nèi)存使用，logstash 默認的堆內(nèi)存是 1G，根據(jù) ECS 集群選擇合適的內(nèi)存，可以加快集群數(shù)據(jù)的遷移效率。

?3. 遷移索引

Logstash 會幫助用戶自動創(chuàng)建索引，但是自動創(chuàng)建的索引和用戶本身的索引會有些許差異，導致最終數(shù)據(jù)的搜索格式不一致，一般索引需要手動創(chuàng)建，保證索引的數(shù)據(jù)完全一致。

以下提供創(chuàng)建索引的 python 腳本，用戶可以使用該腳本創(chuàng)建需要的索引。

create_mapping.py 文件是同步索引的 python 腳本，config.yaml 是集群地址配置文件。

注：使用該腳本需要安裝相關(guān)依賴

yum install -y PyYAML
yum install -y python-requests

拷貝以下代碼保存為 create_mapping.py：

import yaml
import requests
import json
import getopt
import sys

defhelp():
    print
    """
    usage:
    -h/--help print this help.
    -c/--config config file path, default is config.yaml
    
    example:  
    python create_mapping.py -c config.yaml 
    """
defprocess_mapping(index_mapping, dest_index):
    print(index_mapping)
    # remove unnecessary keys
    del index_mapping["settings"]["index"]["provided_name"]
    del index_mapping["settings"]["index"]["uuid"]
    del index_mapping["settings"]["index"]["creation_date"]
    del index_mapping["settings"]["index"]["version"]

    # check alias
    aliases = index_mapping["aliases"]
    for alias inlist(aliases.keys()):
        if alias == dest_index:
            print(
                "source index "+ dest_index +" alias "+ alias +" is the same as dest_index name, will remove this alias.")
            del index_mapping["aliases"][alias]
    if index_mapping["settings"]["index"].has_key("lifecycle"):
        lifecycle = index_mapping["settings"]["index"]["lifecycle"]
        opendistro ={"opendistro":{"index_state_management":
                                         {"policy_id": lifecycle["name"],
                                          "rollover_alias": lifecycle["rollover_alias"]}}}
        index_mapping["settings"].update(opendistro)
        # index_mapping["settings"]["opendistro"]["index_state_management"]["rollover_alias"] = lifecycle["rollover_alias"]
        del index_mapping["settings"]["index"]["lifecycle"]
    print(index_mapping)
    return index_mapping
defput_mapping_to_target(url, mapping, source_index, dest_auth=None):
    headers ={'Content-Type':'application/json'}
    create_resp = requests.put(url, headers=headers, data=json.dumps(mapping), auth=dest_auth)
    if create_resp.status_code !=200:
        print(
            "create index "+ url +" failed with response: "+str(create_resp)+", source index is "+ source_index)
        print(create_resp.text)
        withopen(source_index +".json","w")as f:
            json.dump(mapping, f)
defmain():
    config_yaml ="config.yaml"
    opts, args = getopt.getopt(sys.argv[1:],'-h-c:',['help','config='])
    for opt_name, opt_value in opts:
        if opt_name in('-h','--help'):
            help()
            exit()
        if opt_name in('-c','--config'):
            config_yaml = opt_value

    config_file =open(config_yaml)
    config = yaml.load(config_file)
    source = config["source"]
    source_user = config["source_user"]
    source_passwd = config["source_passwd"]
    source_auth =None
    if source_user !="":
        source_auth =(source_user, source_passwd)
    dest = config["destination"]
    dest_user = config["destination_user"]
    dest_passwd = config["destination_passwd"]
    dest_auth =None
    if dest_user !="":
        dest_auth =(dest_user, dest_passwd)
    print(source_auth)
    print(dest_auth)

    # only deal with mapping list
    if config["only_mapping"]:
        for source_index, dest_index in config["mapping"].iteritems():
            print("start to process source index"+ source_index +", target index: "+ dest_index)
            source_url = source +"/"+ source_index
            response = requests.get(source_url, auth=source_auth)
            if response.status_code !=200:
                print("*** get ElasticSearch message failed. resp statusCode:"+str(
                    response.status_code)+" response is "+ response.text)
                continue
            mapping = response.json()
            index_mapping = process_mapping(mapping[source_index], dest_index)

            dest_url = dest +"/"+ dest_index
            put_mapping_to_target(dest_url, index_mapping, source_index, dest_auth)
            print("process source index "+ source_index +" to target index "+ dest_index +" successed.")
    else:
        # get all indices
        response = requests.get(source +"/_alias", auth=source_auth)
        if response.status_code !=200:
            print("*** get all index failed. resp statusCode:"+str(
                response.status_code)+" response is "+ response.text)
            exit()
        all_index = response.json()
        for index inlist(all_index.keys()):
            if"."in index:
                continue
            print("start to process source index"+ index)
            source_url = source +"/"+ index
            index_response = requests.get(source_url, auth=source_auth)
            if index_response.status_code !=200:
                print("*** get ElasticSearch message failed. resp statusCode:"+str(
                    index_response.status_code)+" response is "+ index_response.text)
                continue
            mapping = index_response.json()

            dest_index = index
            if index in config["mapping"].keys():
                dest_index = config["mapping"][index]
            index_mapping = process_mapping(mapping[index], dest_index)

            dest_url = dest +"/"+ dest_index
            put_mapping_to_target(dest_url, index_mapping, index, dest_auth)
            print("process source index "+ index +" to target index "+ dest_index +" successed.")

if __name__ =='__main__':
    main()

配置文件保存為 config.yaml：

# 源端ES集群地址，加上http://
source: http://ip:port
source_user: "username"
source_passwd: "password"
# 目的端ES集群地址，加上http://
destination: http://ip:port
destination_user: "username"
destination_passwd: "password"

# 是否只處理這個文件中mapping地址的索引
# 如果設(shè)置成true，則只會將下面的mapping中的索引獲取到并在目的端創(chuàng)建
# 如果設(shè)置成false，則會取源端集群的所有索引，除去（.kibana）
# 并且將索引名稱與下面的mapping匹配，如果匹配到使用mapping的value作為目的端的索引名稱
# 如果匹配不到，則使用源端原始的索引名稱
only_mapping: true

# 要遷移的索引，key為源端的索引名字，value為目的端的索引名字
mapping:
    source_index: dest_index

以上代碼和配置文件準備完成，直接執(zhí)行 python create_mapping.py 即可完成索引同步。

索引同步完成可以取目標集群的 kibana 上查看或者執(zhí)行 curl 查看索引遷移情況：

GET _cat/indices?v

?

?

input{
    elasticsearch{
        # 源端地址
        hosts =>  ["ip1:port1","ip2:port2"]
        # 安全集群配置登錄用戶名密碼
        user => "username"
        password => "password"
        # 需要遷移的索引列表，以逗號分隔,支持通配符
        index => "a_*,b_*"
        # 以下三項保持默認即可，包含線程數(shù)和遷移數(shù)據(jù)大小和logstash jvm配置相關(guān)
        docinfo=>true
        slices => 10
        size => 2000
        scroll => "60m"
    }
}

filter {
  # 去掉一些logstash自己加的字段
  mutate {
    remove_field => ["@timestamp", "@version"]
  }
}

output{
    elasticsearch{
        # 目的端es地址
        hosts => ["http://ip:port"]
        # 安全集群配置登錄用戶名密碼
        user => "username"
        password => "password"
 # 目的端索引名稱，以下配置為和源端保持一致
        index => "%{[@metadata][_index]}"
        # 目的端索引type，以下配置為和源端保持一致
        document_type => "%{[@metadata][_type]}"
        # 目標端數(shù)據(jù)的_id，如果不需要保留原_id，可以刪除以下這行，刪除后性能會更好
        document_id => "%{[@metadata][_id]}"
        ilm_enabled => false
        manage_template => false
    }

    # 調(diào)試信息，正式遷移去掉
    stdout { codec => rubydebug { metadata => true }}
}

增量遷移

預處理：

1.@timestamp在 elasticsearch2.0.0beta 版本后棄用

https://www.elastic.co/guide/en/elasticsearch/reference/2.4/mapping-timestamp-field.html

2. 本次對于京辦從金山云機房遷移到京東有孚機房，所涉及到的業(yè)務領(lǐng)域多，各個業(yè)務線中所代表新增記錄的時間戳字段不統(tǒng)一，所涉及到的兼容工作量大，于是考慮通過 elasticsearch 中預處理功能 pipeline 進行預處理添加統(tǒng)一增量標記字段：gmt_created_at，以減少遷移工作的復雜度（各自業(yè)務線可自行評估是否需要此步驟）。

PUT _ingest/pipeline/gmt_created_at
{
  "description":"Adds gmt_created_at timestamp to documents",
  "processors":[
    {
      "set":{
        "field":"_source.gmt_created_at",
        "value":"{{_ingest.timestamp}}"
      }
    }
  ]
}

3. 檢查 pipeline 是否生效

GET _ingest/pipeline/*

4. 各個 index 設(shè)置對應 settings 增加 pipeline 為默認預處理

PUT index_xxxx/_settings
{
  "settings": {
    "index.default_pipeline": "gmt_created_at"
  }
}

5. 檢查新增 settings 是否生效

GET index_xxxx/_settings

?

??增量遷移腳本

schedule-migrate.conf

index：可以使用通配符的方式

query: 增量同步的 DSL，統(tǒng)一 gmt_create_at 為增量同步的特殊標記

schedule: 每分鐘同步一把，"* * * * *"

input {
elasticsearch {
        hosts =>["ip:port"]
        # 安全集群配置登錄用戶名密碼
        user =>"username"
        password =>"password"
        index =>"index_*"
        query =>'{"query":{"range":{"gmt_create_at":{"gte":"now-1m","lte":"now/m"}}}}'
        size =>5000
        scroll =>"5m"
        docinfo =>true
        schedule =>"* * * * *"
      }
}
filter {
     mutate {
      remove_field =>["source", "@version"]
   }
}
output {
    elasticsearch {
        # 目的端es地址
        hosts =>["http://ip:port"]
        # 安全集群配置登錄用戶名密碼
        user =>"username"
        password =>"password"
        index =>"%{[@metadata][_index]}"
        document_type =>"%{[@metadata][_type]}"
        document_id =>"%{[@metadata][_id]}"
        ilm_enabled =>false
        manage_template =>false
    }

# 調(diào)試信息，正式遷移去掉
stdout { codec => rubydebug { metadata =>true}}
}

問題：

[2022-09-20T20:02:16,404][WARN ][logstash.outputs.elasticsearch] Could not index event to Elasticsearch. {:status=>400, 
:action=>["index", {:_id=>"xxx", :_index=>"xxx", :_type=>"joywork_t_work", :routing=>nil}, #], 
:response=>{"index"=>{"_index"=>"xxx", "_type"=>"xxx", "_id"=>"xxx", "status"=>400, 
"error"=>{"type"=>"mapper_parsing_exception", "reason"=>"failed to parse", 
"caused_by"=>{"type"=>"illegal_argument_exception", "reason"=>"[routing] is missing for join field [task_user]"}}}}}

解決方法：

https://discuss.elastic.co/t/an-routing-missing-exception-is-obtained-when-reindex-sets-the-routing-value/155140https://github.com/elastic/elasticsearch/issues/26183

結(jié)合業(yè)務特征，通過在 filter 中加入小量的 ruby 代碼，將_routing 的值取出來，放回 logstah event 中，由此問題得以解決。

示例：