如何在CoreOS上的Docker映像中從快照還原etcd集群？

Question

我在vmware上有一個帶有3個節點的etcd集群（etcd版本3.1.5）的Kubernetes集群（v1.5.6）。 這個etcd節點在vmware上的coreos上的三個docker容器中（在三個主機上）運行。

我嘗試使用以下解決方案備份etcd：

docker run --rm --net=host -v /tmp:/etcd_backup -e ETCDCTL_API=3 quay.io/coreos/etcd:v3.1.5 etcdctl --endpoints=[1.1.1.1:2379,2.2.2.2:2379,3.3.3.3:2379] snapshot save etcd_backup/snapshot.db

備份已成功完成。

我想在另一個vmware環境中從零創建這個kubernetes集群，但是為此我需要從快照還原etcd。

到目前為止，我還沒有在Docker容器中找到適用於etcd的正確解決方案。

我嘗試使用以下方法進行還原，但不幸的是我沒有成功。

首先，我運行以下命令后創建了一個新的etcd節點：

docker run --rm --net=host -v /tmp/etcd_bak:/etcd_backup -e ETCDCTL_API=3 registry:5000/quay.io/coreos/etcd:v3.1.5 etcdctl snapshot restore etcd_backup/snapshot.db --name etcd0 --initial-cluster etcd0=http://etcd0:2380,etcd1=http://etcd1:2380,etcd2=http://etcd2:2380 --initial-cluster-token etcd-cluster-1 --initial-advertise-peer-urls http://etcd0:2380

結果：

2018-06-04 09:25:52.314747 I | etcdserver/membership: added member 7ff5c9c6942f82e [http://etcd0:2380] to cluster 5d1b637f4b7740d5
2018-06-04 09:25:52.314940 I | etcdserver/membership: added member 91b417e7701c2eeb [http://etcd2:2380] to cluster 5d1b637f4b7740d5
2018-06-04 09:25:52.315096 I | etcdserver/membership: added member faeb78734ee4a93d [http://etcd1:2380] to cluster 5d1b637f4b7740d5

不幸的是，什么也沒有發生。

恢復etcd備份的最佳解決方案是什么？

如何創建一個空的etcd群集/節點，如何恢復快照？

Answer 1

根據Etcd Disaster Recovery文檔，您需要使用諸如您的命令從快照還原所有三個etcd節點，然后使用如下命令運行三個節點：

etcd \
  --name m1 \
  --listen-client-urls http://host1:2379 \
  --advertise-client-urls http://host1:2379 \
  --listen-peer-urls http://host1:2380 &

另外，您可以從圖像中提取etcdctl，如下所示：

docker run --rm -v /opt/bin:/opt/bin registry:5000/quay.io/coreos/etcd:v3.1.5 cp /usr/local/bin/etcdctl /opt/bin

然后使用etcdctl還原快照：

# ETCDCTL_API=3 ./etcdctl snapshot restore snapshot.db \
  --name m1 \
  --initial-cluster m1=http://host1:2380,m2=http://host2:2380,m3=http://host3:2380 \
  --initial-cluster-token etcd-cluster-1 \
  --initial-advertise-peer-urls http://host1:2380 \
  --data-dir /var/lib/etcd

這會將快照還原到/ var / lib / etcd目錄。 然后從docker啟動etcd，不要忘記將/ var / lib / etcd掛載到您的容器中，並為其指定--data-dir。

Answer 2

kubernetes中的Ectd在Docker容器中運行，這是我恢復群集的操作：

• 檢索Etcd集群元數據

   docker inspect etcd1 

  您將獲得如下所示的內容：

   "Binds": [ "/etc/ssl/certs:/etc/ssl/certs:ro", "/etc/ssl/etcd/ssl:/etc/ssl/etcd/ssl:ro", "/var/lib/etcd:/var/lib/etcd:rw" ], ... "Env": [ "ETCD_DATA_DIR=/var/lib/etcd", "ETCD_ADVERTISE_CLIENT_URLS=https://172.16.60.1:2379", "ETCD_INITIAL_ADVERTISE_PEER_URLS=https://172.16.60.1:2380", "ETCD_INITIAL_CLUSTER_STATE=existing", "ETCD_METRICS=basic", "ETCD_LISTEN_CLIENT_URLS=https://172.16.60.1:2379,https://127.0.0.1:2379", "ETCD_ELECTION_TIMEOUT=5000", "ETCD_HEARTBEAT_INTERVAL=250", "ETCD_INITIAL_CLUSTER_TOKEN=k8s_etcd", "ETCD_LISTEN_PEER_URLS=https://172.16.60.1:2380", "ETCD_NAME=etcd1", "ETCD_PROXY=off", "ETCD_INITIAL_CLUSTER=etcd1=https://172.16.60.1:2380,etcd2=https://172.16.60.2:2380,etcd3=https://172.16.60.2:2380", "ETCD_AUTO_COMPACTION_RETENTION=8", "ETCD_TRUSTED_CA_FILE=/etc/ssl/etcd/ssl/ca.pem", "ETCD_CERT_FILE=/etc/ssl/etcd/ssl/member-node01.pem", "ETCD_KEY_FILE=/etc/ssl/etcd/ssl/member-node01-key.pem", "ETCD_PEER_TRUSTED_CA_FILE=/etc/ssl/etcd/ssl/ca.pem", "ETCD_PEER_CERT_FILE=/etc/ssl/etcd/ssl/member-node01.pem", "ETCD_PEER_KEY_FILE=/etc/ssl/etcd/ssl/member-node01-key.pem", "ETCD_PEER_CLIENT_CERT_AUTH=true", "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" ], "Cmd": [ "/usr/local/bin/etcd" ], 

• 將etcd snapshotdb復制到其他etcd節點

   scp snapshotdb_20180913 node02:/root/ scp snapshotdb_20180913 node03:/root/ 

• 用原始信息重建新集群

   # etcd1 docker stop etcd1 rm -rf /var/lib/etcd ETCDCTL_API=3 etcdctl snapshot restore snapshotdb_20180913 \\ --cacert /etc/ssl/etcd/ssl/ca.pem \\ --cert /etc/ssl/etcd/ssl/member-node01.pem \\ --key /etc/ssl/etcd/ssl/member-node01-key.pem \\ --name etcd1 \\ --initial-cluster etcd1=https://node01:2380,etcd2=https://node02:2380,etcd3=https://node03:2380 \\ --initial-cluster-token k8s_etcd \\ --initial-advertise-peer-urls https://node01:2380 \\ --data-dir /var/lib/etcd # etcd2 docker stop etcd2 rm -rf /var/lib/etcd ETCDCTL_API=3 etcdctl snapshot restore snapshotdb_20180913 \\ --cacert /etc/ssl/etcd/ssl/ca.pem \\ --cert /etc/ssl/etcd/ssl/member-node02.pem \\ --key /etc/ssl/etcd/ssl/member-node02-key.pem \\ --name etcd2 \\ --initial-cluster etcd1=https://node01:2380,etcd2=https://node02:2380,etcd3=https://node03:2380 \\ --initial-cluster-token k8s_etcd \\ --initial-advertise-peer-urls https://node02:2380 \\ --data-dir /var/lib/etcd # etcd3 docker stop etcd3 rm -rf /var/lib/etcd ETCDCTL_API=3 etcdctl snapshot restore snapshotdb_20180913 \\ --cacert /etc/ssl/etcd/ssl/ca.pem \\ --cert /etc/ssl/etcd/ssl/member-node03.pem \\ --key /etc/ssl/etcd/ssl/member-node03-key.pem \\ --name etcd3 \\ --initial-cluster etcd1=https://node01:2380,etcd2=https://node02:2380,etcd3=https://node03:2380 \\ --initial-cluster-token k8s_etcd \\ --initial-advertise-peer-urls https://node03:2380 \\ --data-dir /var/lib/etcd 

• 啟動容器並檢查集群狀態

   cd /etc/ssl/etcd/ssl etcdctl \\ --endpoints=https://node01:2379 \\ --ca-file=./ca.pem \\ --cert-file=./member-node01.pem \\ --key-file=./member-node01-key.pem \\ member list