[TOC] 场景：做etcd数据镜像的时候出现如下错误 Error: etcdserver: mvcc: database space exceeded 通过查找官方文档 https://etcd.io/docs/v3.4/faq/#what-does-mvcc-database-space-exceeded-mean-and-how-do-i-fix-it 确定解决方案，通过执行命令压缩etcd空间并且整理空间碎片即可 ## 查看节点使用dbsize情况 ```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 | | +-----------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+ ``` ## 获取当前版本 ```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` 只能写一个节点。 ## 压缩历史版本 ```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` 只能写一个节点，压缩版本但为释放空间。 ## 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` 只能写一个节点，实际清理空间内存。 ## 验证dbsize 命令行查看的结果 ```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 | | +-----------------------------+------------------+---------+---------+-----------+------------+-----------+------------+--------------------+--------+ ``` 监控系统查看的结果