[TOC] 場景：做etcd數據鏡像的時候出現如下錯誤 Error: etcdserver: mvcc: database space exceeded 通過查找官方文檔 https://etcd.io/docs/v3.4/faq/#what-does-mvcc-database-space-exceeded-mean-and-how-do-i-fix-it 確定解決方案，通過執行命令壓縮etcd空間并且整理空間碎片即可 ## 查看節點使用dbsize情況 ```shell $ etcdctl --cacert /data/etcd/certs/ca.pem --cert /data/etcd/certs/etcd.pem --key /data/etcd/certs/etcd-key.pem --endpoints=https://192.168.31.95:2379,https://192.168.31.78:2379,https://192.168.31.253:2379 -w table endpoint status +-----------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+ | ENDPOINT | ID | VERSION | DB SIZE | IS LEADER | IS LEARNER | RAFT TERM | RAFT INDEX | RAFT APPLIED INDEX | ERRORS | +-----------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+ | https://192.168.31.95:2379 | a691716a7d43ab3b | 3.4.16 | 20 MB | false | false | 422 | 6647577 | 6647577 | | | https://192.168.31.78:2379 | f833bfe4fb9c10d3 | 3.4.16 | 4.7 MB | false | false | 422 | 6647577 | 6647577 | | | https://192.168.31.253:2379 | 10f52b9841a7c5f5 | 3.4.16 | 20 MB | true | false | 422 | 6647577 | 6647577 | | +-----------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+ ``` ## 獲取當前版本 ```shell $ rev=$(etcdctl --cacert /data/etcd/certs/ca.pem --cert /data/etcd/certs/etcd.pem --key /data/etcd/certs/etcd-key.pem --endpoints=https://192.168.31.95:2379 endpoint status --write-out="json" | egrep -o '"revision":[0-9]*' | egrep -o '[0-9].*') $ echo $rev ``` > 注意：`--endpoints` 只能寫一個節點。 ## 壓縮歷史版本 ```shell $ etcdctl --cacert /data/etcd/certs/ca.pem --cert /data/etcd/certs/etcd.pem --key /data/etcd/certs/etcd-key.pem --endpoints=https://192.168.31.95:2379 compact $rev compacted revision 5837375 ``` > 注意：`--endpoints` 只能寫一個節點，壓縮版本但為釋放空間。 ## 碎片整理 ```shell $ etcdctl --cacert /data/etcd/certs/ca.pem --cert /data/etcd/certs/etcd.pem --key /data/etcd/certs/etcd-key.pem --endpoints=https://192.168.31.95:2379 defrag Finished defragmenting etcd member[https://192.168.31.95:2379] ``` > 注意：`--endpoints` 只能寫一個節點，實際清理空間內存。 ## 驗證dbsize 命令行查看的結果 ```shell $ etcdctl --cacert /data/etcd/certs/ca.pem --cert /data/etcd/certs/etcd.pem --key /data/etcd/certs/etcd-key.pem --endpoints=https://192.168.31.95:2379,https://192.168.31.78:2379,https://192.168.31.253:2379 -w table endpoint status +-----------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+ | ENDPOINT | ID | VERSION | DB SIZE | IS LEADER | IS LEARNER | RAFT TERM | RAFT INDEX | RAFT APPLIED INDEX | ERRORS | +-----------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+ | https://192.168.31.95:2379 | a691716a7d43ab3b | 3.4.16 | 2.2 MB | false | false | 422 | 6647941 | 6647941 | | | https://192.168.31.78:2379 | f833bfe4fb9c10d3 | 3.4.16 | 4.7 MB | false | false | 422 | 6647941 | 6647941 | | | https://192.168.31.253:2379 | 10f52b9841a7c5f5 | 3.4.16 | 20 MB | true | false | 422 | 6647941 | 6647941 | | +-----------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+ ``` 監控系統查看的結果