3. etcdctl 常用命令

1. etcdctl的安装

etcdctl的二进制文件可以在选择对应的版本下载，例如可以执行以下install_etcdctl.sh的脚本，修改其中的版本信息。

2. etcdctl V3

使用etcdctlv3的版本时，需设置环境变量ETCDCTL_API=3。

export ETCDCTL_API=3
或者在`/etc/profile`文件中添加环境变量
vi /etc/profile
...
ETCDCTL_API=3
...
source /etc/profile

查看当前etcdctl的版本信息etcdctl version。

[root@k8s-dbg-master-1 etcd]# etcdctl version
etcdctl version: 3.3.4
API version: 3.3

更多命令帮助可以查询etcdctl —help。

[root@k8s-dbg-master-1 etcd]# etcdctl --help
NAME:
    etcdctl - A simple command line client for etcd3.
USAGE:
    etcdctl
VERSION:
    3.3.4
API VERSION:
    3.3
COMMANDS:
    get            Gets the key or a range of keys
    put            Puts the given key into the store
    del            Removes the specified key or range of keys [key, range_end)
    txn            Txn processes all the requests in one transaction
    compaction        Compacts the event history in etcd
    alarm disarm        Disarms all alarms
    alarm list        Lists all alarms
    defrag            Defragments the storage of the etcd members with given endpoints
    endpoint health        Checks the healthiness of endpoints specified in `--endpoints` flag
    endpoint status        Prints out the status of endpoints specified in `--endpoints` flag
    endpoint hashkv        Prints the KV history hash for each endpoint in --endpoints
    move-leader        Transfers leadership to another etcd cluster member.
    watch            Watches events stream on keys or prefixes
    version            Prints the version of etcdctl
    lease grant        Creates leases
    lease revoke        Revokes leases
    lease timetolive    Get lease information
    lease list        List all active leases
    lease keep-alive    Keeps leases alive (renew)
    member add        Adds a member into the cluster
    member update        Updates a member in the cluster
    member list        Lists all members in the cluster
    snapshot save        Stores an etcd node backend snapshot to a given file
    snapshot restore    Restores an etcd member snapshot to an etcd directory
    snapshot status        Gets backend snapshot status of a given file
    make-mirror        Makes a mirror at the destination etcd cluster
    migrate            Migrates keys in a v2 store to a mvcc store
    lock            Acquires a named lock
    elect            Observes and participates in leader election
    auth enable        Enables authentication
    auth disable        Disables authentication
    user add        Adds a new user
    user delete        Deletes a user
    user get        Gets detailed information of a user
    user list        Lists all users
    user passwd        Changes password of user
    user grant-role        Grants a role to a user
    user revoke-role    Revokes a role from a user
    role add        Adds a new role
    role delete        Deletes a role
    role get        Gets detailed information of a role
    role list        Lists all roles
    role grant-permission    Grants a key to a role
    role revoke-permission    Revokes a key from a role
    check perf        Check the performance of the etcd cluster
    help            Help about any command
OPTIONS:
      --cacert=""                verify certificates of TLS-enabled secure servers using this CA bundle
      --cert=""                    identify secure client using this TLS certificate file
      --command-timeout=5s            timeout for short running command (excluding dial timeout)
      --debug[=false]                enable client-side debug logging
      --dial-timeout=2s                dial timeout for client connections
  -d, --discovery-srv=""            domain name to query for SRV records describing cluster endpoints
      --endpoints=[127.0.0.1:2379]        gRPC endpoints
      --hex[=false]                print byte strings as hex encoded strings
      --insecure-discovery[=true]        accept insecure SRV records describing cluster endpoints
      --insecure-skip-tls-verify[=false]    skip server certificate verification
      --insecure-transport[=true]        disable transport security for client connections
      --keepalive-time=2s            keepalive time for client connections
      --keepalive-timeout=6s            keepalive timeout for client connections
      --key=""                    identify secure client using this TLS key file
      --user=""                    username[:password] for authentication (prompt if password is not supplied)
  -w, --write-out="simple"            set the output format (fields, json, protobuf, simple, table)

3. etcdctl 常用命令

etcdctl --endpoints=$ENDPOINTS put foo "Hello World!"

2、查

etcdctl --endpoints=$ENDPOINTS get foo
etcdctl --endpoints=$ENDPOINTS --write-out="json" get foo

基于相同前缀查找

etcdctl --endpoints=$ENDPOINTS put web1 value1
etcdctl --endpoints=$ENDPOINTS put web2 value2
etcdctl --endpoints=$ENDPOINTS put web3 value3
etcdctl --endpoints=$ENDPOINTS get web --prefix

列出所有的key

3、删**

etcdctl --endpoints=$ENDPOINTS put key myvalue
etcdctl --endpoints=$ENDPOINTS put k2 value2
etcdctl --endpoints=$ENDPOINTS del k --prefix

etcdctl --write-out=table --endpoints=$ENDPOINTS endpoint status
+------------------+------------------+---------+---------+-----------+-----------+------------+
|     ENDPOINT     |        ID        | VERSION | DB SIZE | IS LEADER | RAFT TERM | RAFT INDEX |
+------------------+------------------+---------+---------+-----------+-----------+------------+
| 10.240.0.17:2379 | 4917a7ab173fabe7 | 3.0.0   | 45 kB   | true      |         4 |      16726 |
| 10.240.0.18:2379 | 59796ba9cd1bcd72 | 3.0.0   | 45 kB   | false     |         4 |      16726 |
| 10.240.0.19:2379 | 94df724b66343e6c | 3.0.0   | 45 kB   | false     |         4 |      16726 |
+------------------+------------------+---------+---------+-----------+-----------+------------+
etcdctl --endpoints=$ENDPOINTS endpoint health
10.240.0.17:2379 is healthy: successfully committed proposal: took = 3.345431ms
10.240.0.19:2379 is healthy: successfully committed proposal: took = 3.767967ms
10.240.0.18:2379 is healthy: successfully committed proposal: took = 4.025451ms

跟集群成员相关的命令如下：

    member add            Adds a member into the cluster
    member remove        Removes a member from the cluster
    member update        Updates a member in the cluster
    member list            Lists all members in the cluster

例如 etcdctl member list列出集群成员的命令。

4. etcdctl get

使用etcdctl {command} --help可以查看具体命令的帮助信息。

# etcdctl get --help
NAME:
    get - Gets the key or a range of keys
USAGE:
    etcdctl get [options] <key> [range_end]
OPTIONS:
      --consistency="l"            Linearizable(l) or Serializable(s)
      --from-key[=false]        Get keys that are greater than or equal to the given key using byte compare
      --keys-only[=false]        Get only the keys
      --limit=0                Maximum number of results
      --order=""            Order of results; ASCEND or DESCEND (ASCEND by default)
      --prefix[=false]            Get keys with matching prefix
      --print-value-only[=false]    Only write values when using the "simple" output format
      --rev=0                Specify the kv revision
      --sort-by=""            Sort target; CREATE, KEY, MODIFY, VALUE, or VERSION
GLOBAL OPTIONS:
      --cacert=""                verify certificates of TLS-enabled secure servers using this CA bundle
      --cert=""                    identify secure client using this TLS certificate file
      --command-timeout=5s            timeout for short running command (excluding dial timeout)
      --debug[=false]                enable client-side debug logging
      --dial-timeout=2s                dial timeout for client connections
      --endpoints=[127.0.0.1:2379]        gRPC endpoints
      --hex[=false]                print byte strings as hex encoded strings
      --insecure-skip-tls-verify[=false]    skip server certificate verification
      --insecure-transport[=true]        disable transport security for client connections
      --key=""                    identify secure client using this TLS key file
      --user=""                    username[:password] for authentication (prompt if password is not supplied)

文章参考：

etcdctl命令工具-V3

1. etcdctl的安装

2. etcdctl V3

3. etcdctl 常用命令

4. etcdctl get