Backup e recuperação do Cassandra

Esta seção discute como configurar o backup e a recuperação de dados para o anel de banco de dados do Apache Cassandra instalado no plano de ambiente de execução da Apigee híbrida. Consulte também Banco de dados do Cassandra.

O que você precisa saber sobre os backups do Cassandra

O Cassandra é um banco de dados replicado configurado para ter pelo menos três cópias dos dados em cada região ou data center. O Cassandra usa replicação de streaming e reparos de leitura para manter as réplicas de dados em cada região ou data center em um determinado ponto.

No ambiente híbrido, os backups do Cassandra não estão ativados por padrão. No entanto, é recomendável ativar os backups do Cassandra caso seus dados sejam excluídos acidentalmente.

O que é incluído no backup?

A configuração de backup descrita neste tópico faz backup das seguintes entidades:

  • Esquema do Cassandra, incluindo o esquema do usuário (definições de keyspace da Apigee).
  • Informações do token de partição do Cassandra por nó.
  • Um snapshot dos dados do Cassandra.

Onde os dados de backup são armazenados?

Os dados de backup são armazenados em um bucket do Google Cloud Storage (GCS) que você precisa criar. A criação e a configuração do bucket são abordadas neste tópico.

Como programar backups do Cassandra

Os backups são programados como cron jobs no plano do ambiente de execução. Para programar backups do Cassandra, siga estas etapas:

  1. Execute o seguinte comando create-service-account para criar uma conta de serviço do GCP (SA) com o papel padrão roles/storage.objectAdmin. Esse papel de SA permite gravar dados de backup no Google Cloud Storage (GCS). Execute o seguinte comando no diretório raiz da instalação híbrida: 
    ./tools/create-service-account apigee-cassandra output-dir
    Exemplo: 
    ./tools/create-service-account apigee-cassandra ./service-accounts
    Para mais informações sobre contas de serviço do GCP, consulte Como criar e gerenciar contas de serviço.
  2. O comando create-service-account salva um arquivo JSON que contém a chave privada da conta de serviço. O arquivo é salvo no mesmo diretório em que o comando é executado. Você precisará do caminho desse arquivo nas etapas a seguir.
  3. Crie um bucket do GCS. Especifique uma política de retenção de dados razoável para o bucket. A Apigee recomenda uma política de retenção de dados de 15 dias.
  4. Abra o arquivo overrides.yaml.
  5. Adicione as seguintes propriedades cassandra.backup para ativar o backup. Não remova nenhuma das propriedades já configuradas. 
    cassandra:
  ...

  backup:
    enabled: true
    serviceAccountPath: sa_json_file_path
    dbStorageBucket: gcs_bucket_path
    schedule: backup_schedule_code

  ...
    Em que:
    Propriedade Descrição
    enabled O backup está desativado por padrão. É preciso definir essa propriedade como true
    serviceAccountPath O caminho no sistema de arquivos para o arquivo JSON da conta de serviço que foi salvo quando você executou ./tools/create-service-account
    dbStorageBucket Caminho do bucket de armazenamento do GCS neste formato: gs://bucket_name. O gs:// é obrigatório.
    schedule O horário de início do backup, especificado na sintaxe padrão de crontab. Padrão: 0 2 * * *

    Observação: evite programar um backup que inicie pouco tempo depois de aplicar a configuração de backup ao cluster. Quando você aplica a configuração de backup, o Kubernetes recria os nós do Cassandra. Se o backup começar antes da reinicialização dos nós (possivelmente vários minutos), ele falhará.

    Exemplo: 
    ...

cassandra:
  storage:
    type: gcepd
    capacity: 50Gi
    gcepd:
      replicationType: regional-pd
  sslRootCAPath: "/Users/myhome/ssh/cassandra.crt"
  sslCertPath: "/Users/myhome/ssh/cassandra.crt"
  sslKeyPath: "/Users/myhome/ssh/cassandra.key"
  auth:
    default:
      password: "abc123"
    admin:
      password: "abc234"
    ddl:
      password: "abc345"
    dml:
      password: "abc456"
  nodeSelector:
    key: cloud.google.com/gke-nodepool
    value: apigee-data
  backup:
    enabled: true
    serviceAccountPath: "/Users/myhome/.ssh/my_cassandra_backup.json"
    dbStorageBucket: "gs://myname-cassandra-backup"
    schedule: "45 23 * * 6"

  ...
  6. Aplique as alterações de configuração ao novo cluster. Exemplo: 
    ./apigeectl apply -c 2_cassandra -v beta2

Restauração de backups

A restauração recebe os dados do local de backup e os restaura em um novo cluster do Cassandra com o mesmo número de pods. O novo cluster precisa ter um namespace diferente do cluster do plano de ambiente de execução.

Para restaurar backups do Cassandra:

  1. Crie um novo cluster do Kubernetes com um novo namespace. Não é possível usar o mesmo cluster/namespace que você utilizou para a instalação híbrida original.
  2. No diretório raiz da instalação híbrida, crie um novo arquivo overrides-restore.yaml.
  3. Copie a configuração completa do Cassandra do arquivo overrides.yaml original para o novo.
  4. Adicione um elemento de namespace. Não use o mesmo namespace usado no cluster original.
    5. namespace: your-restore-namespace

cassandra:
  storage:
    type: gcepd
    capacity: 50Gi
    gcepd:
      replicationType: regional-pd
  nodeSelector:
    key: cloud.google.com/gke-nodepool
    value: apigee-data
  sslRootCAPath: path_to_root_ca_file
  sslCertPath: path_to_ssl_cert_file
  sslKeyPath: path_to_ssl_key_file
  auth:
    default:
      password: your_cassandra_password
    admin:
      password: admin_password
    ddl:
      password: ddl_password
    dml:
      password: dml_password

  restore:
      enabled: true
      snapshotTimestamp: timestamp
      serviceAccountPath: sa_json_file_path
      dbStorageBucket: gcs_bucket_path
      image:
        pullPolicy: Always
    Em que:
    Propriedade Descrição
    ssl*Path, auth.* Use as mesmas credenciais de autenticação TLS que você usou para criar o banco de dados original do Cassandra.
    snapshotTimestamp O carimbo de data/hora do snapshot de backup a ser restaurado.
    serviceAccountPath O caminho no seu sistema de arquivos para a conta de serviço criada para o backup.
    dbStorageBucket Caminho do bucket de armazenamento do GCS em que seu backup está armazenado, neste formato: gs://bucket_name. O gs:// é obrigatório.
    Exemplo: 
    namespace: cassandra-restore

cassandra:
  storage:
    type: gcepd
    capacity: 50Gi
    gcepd:
      replicationType: regional-pd
  sslRootCAPath: "/Users/myhome/ssh/cassandra.crt"
  sslCertPath: "/Users/myhome/ssh/cassandra.crt"
  sslKeyPath: "/Users/myhome/ssh/cassandra.key"
  auth:
    default:
      password: "abc123"
    admin:
      password: "abc234"
    ddl:
      password: "abc345"
    dml:
      password: "abc456"
  nodeSelector:
    key: cloud.google.com/gke-nodepool
    value: apigee-data
  restore:
    enabled: true
    snapshotTimestamp: "20190417002207"
    serviceAccountPath: "/Users/myhome/.ssh/my_cassandra_backup.json"
    dbStorageBucket: "gs://myname-cassandra-backup"
    image:
      pullPolicy: Always

    Em que snapshotTimestamp é o carimbo de data/hora associado ao backup que você está restaurando.

  5. Crie o novo cluster do Cassandra: 
      ./apigeectl apply -c 2_cassandra -v beta2 -f ./overrides-restore.yaml
  ./apigeectl apply -c 2_cassandra-role -v beta2

Como ver os registros de restauração

Verifique os registros do job de restauração e o grep para error para garantir que o registro de restauração não tenha erros.

Verificar se a restauração foi concluída

Para verificar se a operação de restauração foi concluída: 

kubectl get pods

NAME                           READY     STATUS      RESTARTS   AGE
apigee-cassandra-0             1/1       Running     0          1h
apigee-cassandra-1             1/1       Running     0          1h
apigee-cassandra-2             1/1       Running     0          59m
apigee-cassandra-restore-b4lgf 0/1       Completed   0          51m

Ver os registros de restauração

Para ver os registros de restauração: 

kubectl logs -f apigee-cassandra-restore-b4lgf

Restore Logs:

Activated service account credentials for: [apigee-cassandra-backup-svc@gce-myusername.iam.gserviceaccount.com]
to download file gs://gce-myusername-apigee-cassandra-backup/apigeecluster/dc-1/backup_20190405011309_schema.tgz
INFO: download sucessfully extracted the backup files from gs://gce-myusername-apigee-cassandra-backup/apigeecluster/dc-1
finished downloading schema.cql
to create schema from 10.32.0.28

Warnings :
dclocal_read_repair_chance table option has been deprecated and will be removed in version 4.0

dclocal_read_repair_chance table option has been deprecated and will be removed in version 4.0

Warnings :
dclocal_read_repair_chance table option has been deprecated and will be removed in version 4.0

dclocal_read_repair_chance table option has been deprecated and will be removed in version 4.0

INFO: the schema has been restored
starting apigee-cassandra-0 in default
starting apigee-cassandra-1 in default
starting apigee-cassandra-2 in default
84 95 106
waiting on waiting nodes $pid to finish  84
Activated service account credentials for: [apigee-cassandra-backup-svc@gce-myusername.iam.gserviceaccount.com]
Activated service account credentials for: [apigee-cassandra-backup-svc@gce-myusername.iam.gserviceaccount.com]
Activated service account credentials for: [apigee-cassandra-backup-svc@gce-myusername.iam.gserviceaccount.com]
INFO: restore downloaded  tarball and extracted the file from  gs://gce-myusername-apigee-cassandra-backup/apigeecluster/dc-1
INFO: restore downloaded  tarball and extracted the file from  gs://gce-myusername-apigee-cassandra-backup/apigeecluster/dc-1
INFO: restore downloaded  tarball and extracted the file from  gs://gce-myusername-apigee-cassandra-backup/apigeecluster/dc-1
INFO  12:02:28 Configuration location: file:/etc/cassandra/cassandra.yaml
…...

INFO  12:02:41 [Stream #e013ee80-5863-11e9-8458-353e9e3cb7f9] All sessions completed

Summary statistics:
   Connections per host    : 3
   Total files transferred : 2
   Total bytes transferred : 0.378KiB
   Total duration          : 5048 ms
   Average transfer rate   : 0.074KiB/s
   Peak transfer rate      : 0.075KiB/s

progress: [/10.32.1.155]0:1/1 100% 1:1/1 100% [/10.32.0.28]1:1/1 100% 0:1/1 100% [/10.32.3.220]0:1/1 100% 1:1/1 100% total: 100% 0.000KiB/s (avg: 0.074KiB/s)
INFO  12:02:41 [Stream #e013ee80-5863-11e9-8458-353e9e3cb7f9] All sessions completed
progress: [/10.32.1.155]0:1/1 100% 1:1/1 100% [/10.32.0.28]1:1/1 100% 0:1/1 100% [/10.32.3.220]0:1/1 100% 1:1/1 100% total: 100% 0.000KiB/s (avg: 0.074KiB/s)
INFO  12:02:41 [Stream #e013ee80-5863-11e9-8458-353e9e3cb7f9] All sessions completed
INFO  12:02:41 [Stream #e013ee80-5863-11e9-8458-353e9e3cb7f9] All sessions completed
INFO: ./apigee/data/cassandra/data/ks1/user-9fbae960571411e99652c7b15b2db6cc restored successfully
INFO: Restore 20190405011309 completed
INFO: ./apigee/data/cassandra/data/ks1/user-9fbae960571411e99652c7b15b2db6cc restored successfully
INFO: Restore 20190405011309 completed
waiting on waiting nodes $pid to finish  106
Restore finished

Verificar o job de backup

Também é possível verificar o job de backup depois que o cron job de backup estiver programado. Depois que o cron job for programado, você verá algo mais ou menos assim: 

kubectl get pods
NAME                        READY     STATUS      RESTARTS   AGE
apigee-cassandra-0          1/1       Running     0          2h
apigee-cassandra-1          1/1       Running     0          2h
apigee-cassandra-2          1/1       Running     0          2h
apigee-cassandra-backup-1554515580-pff6s   0/1       Running     0          54s

Verificar os registros de backup

O job de backup:

  • cria um arquivo schema.cql;
  • faz upload dele para seu bucket de armazenamento;
  • repete o nó para fazer backup dos dados e fazer upload deles ao mesmo tempo;
  • aguarda até que todos os dados sejam enviados.
kubectl logs -f apigee-cassandra-backup-1554515580-pff6s

myusername-macbookpro:cassandra-backup-utility myusername$ kubectl logs -f apigee-cassandra-backup-1554577680-f9sc4
starting apigee-cassandra-0 in default
starting apigee-cassandra-1 in default
starting apigee-cassandra-2 in default
35 46 57
waiting on process  35
Activated service account credentials for: [apigee-cassandra-backup-svc@gce-myusername.iam.gserviceaccount.com]
Activated service account credentials for: [apigee-cassandra-backup-svc@gce-myusername.iam.gserviceaccount.com]
Activated service account credentials for: [apigee-cassandra-backup-svc@gce-myusername.iam.gserviceaccount.com]
Requested creating snapshot(s) for [all keyspaces] with snapshot name [20190406190808] and options {skipFlush=false}
Snapshot directory: 20190406190808
INFO: backup created cassandra snapshot 20190406190808
tar: Removing leading `/' from member names
/apigee/data/cassandra/data/ks1/mytest3-37bc2df0587811e98e8d875b0ed64754/snapshots/
/apigee/data/cassandra/data/ks1/mytest3-37bc2df0587811e98e8d875b0ed64754/snapshots/20190406190808/
/apigee/data/cassandra/data/ks1/mytest3-37bc2df0587811e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-Data.db
Requested creating snapshot(s) for [all keyspaces] with snapshot name [20190406190808] and options {skipFlush=false}
Requested creating snapshot(s) for [all keyspaces] with snapshot name [20190406190808] and options {skipFlush=false}
Snapshot directory: 20190406190808
INFO: backup created cassandra snapshot 20190406190808
tar: Removing leading `/' from member names
/apigee/data/cassandra/data/system/hints-2666e20573ef38b390fefecf96e8f0c7/snapshots/
/apigee/data/cassandra/data/system/hints-2666e20573ef38b390fefecf96e8f0c7/snapshots/20190406190808/
/apigee/data/cassandra/data/system/hints-2666e20573ef38b390fefecf96e8f0c7/snapshots/20190406190808/manifest.json
/apigee/data/cassandra/data/system/prepared_statements-18a9c2576a0c3841ba718cd529849fef/snapshots/
/apigee/data/cassandra/data/system/prepared_statements-18a9c2576a0c3841ba718cd529849fef/snapshots/20190406190808/
/apigee/data/cassandra/data/system/prepared_statements-18a9c2576a0c3841ba718cd529849fef/snapshots/20190406190808/manifest.json
/apigee/data/cassandra/data/system/range_xfers-55d764384e553f8b9f6e676d4af3976d/snapshots/
/apigee/data/cassandra/data/system/range_xfers-55d764384e553f8b9f6e676d4af3976d/snapshots/20190406190808/
/apigee/data/cassandra/data/system/range_xfers-55d764384e553f8b9f6e676d4af3976d/snapshots/20190406190808/manifest.json
/apigee/data/cassandra/data/system/peer_events-59dfeaea8db2334191ef109974d81484/snapshots/
/apigee/data/cassandra/data/system/peer_events-59dfeaea8db2334191ef109974d81484/snapshots/20190406190808/
/apigee/data/cassandra/data/system/peer_events-59dfeaea8db2334191ef109974d81484/snapshots/20190406190808/manifest.json
/apigee/data/cassandra/data/system/built_views-4b3c50a9ea873d7691016dbc9c38494a/snapshots/
/apigee/data/cassandra/data/system/built_views-4b3c50a9ea873d7691016dbc9c38494a/snapshots/20190406190808/
/apigee/data/cassandra/data/system/built_views-4b3c50a9ea873d7691016dbc9c38494a/snapshots/20190406190808/manifest.json
……
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-3-big-Filter.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-2-big-CompressionInfo.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-2-big-Index.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-3-big-Statistics.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-2-big-Data.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-Index.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-Statistics.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-2-big-TOC.txt
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-2-big-Statistics.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-Summary.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-Filter.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-2-big-Summary.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-3-big-Index.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/manifest.json
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-2-big-Filter.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-2-big-Digest.crc32
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-3-big-Summary.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-3-big-Data.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-TOC.txt
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/schema.cql
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-3-big-CompressionInfo.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-Digest.crc32
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-3-big-TOC.txt
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-Data.db
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-3-big-Digest.crc32
/apigee/data/cassandra/data/ks2/user-d6d39d70586311e98e8d875b0ed64754/snapshots/20190406190808/mc-1-big-CompressionInfo.db
……
/tmp/tokens.txt
/ [1 files][    0.0 B/    0.0 B]
Operation completed over 1 objects.
/ [1 files][    0.0 B/    0.0 B]
Operation completed over 1 objects.
INFO: backup created tarball and transfered the file to gs://gce-myusername-apigee-cassandra-backup/apigeecluster/dc-1
INFO: removing cassandra snapshot
INFO: backup created tarball and transfered the file to gs://gce-myusername-apigee-cassandra-backup/apigeecluster/dc-1
INFO: removing cassandra snapshot
Requested clearing snapshot(s) for [all keyspaces]
INFO: Backup 20190406190808 completed
waiting on process  46
Requested clearing snapshot(s) for [all keyspaces]
INFO: Backup 20190406190808 completed
Requested clearing snapshot(s) for [all keyspaces]
waiting on process  57
INFO: Backup 20190406190808 completed
waiting result
to get schema from 10.32.0.28
INFO: /tmp/schema.cql has been generated
Activated service account credentials for: [apigee-cassandra-backup-svc@gce-myusername.iam.gserviceaccount.com]
tar: removing leading '/' from member names
tmp/schema.cql
Copying from ...
/ [1 files][    0.0 B/    0.0 B]
Operation completed over 1 objects.
INFO: backup created tarball and transfered the file to gs://gce-myusername-apigee-cassandra-backup/apigeecluster/dc-1
finished uploading schema.cql