轉載自胡偉煌的博客
使用etcdctl指令可以操作etcd集羣，檢查集羣狀態等
環境變量設置
使用etcdctlv3的版本時，需設置環境變量ETCDCTL_API=3。
export ETCDCTL_API=3
或者在/etc/profile`文件中添加環境變量
vi /etc/profile
...
ETCDCTL_API=3
...
source /etc/profile
查看當前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
更多命令幫助可以查詢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 remove Removes a member from 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)
etcdctl 常用命令
指定etcd集羣
HOST_1=10.240.0.17
HOST_2=10.240.0.18
HOST_3=10.240.0.19
ENDPOINTS=$HOST_1:2379,$HOST_2:2379,$HOST_3:2379
增刪改查
1、增
etcdctl --endpoints=$ENDPOINTS put foo "Hello World!"
2、查
etcdctl --endpoints=$ENDPOINTS get foo
etcdctl --endpoints=$ENDPOINTS --write-out="json" get foo
基於相同前綴查找
etcdctl --endpoints=$ENDPOINTS put web1 value1
etcdctl --endpoints=$ENDPOINTS put web2 value2
etcdctl --endpoints=$ENDPOINTS put web3 value3
etcdctl --endpoints=$ENDPOINTS get web --prefix
3、刪
etcdctl --endpoints=$ENDPOINTS put key myvalue
etcdctl --endpoints=$ENDPOINTS del key
etcdctl --endpoints=$ENDPOINTS put k1 value1
etcdctl --endpoints=$ENDPOINTS put k2 value2
etcdctl --endpoints=$ENDPOINTS del k --prefix
4、監聽
watch
監測一個鍵值的變化，一旦鍵值發生更新，就會輸出最新的值並退出。
例如，用戶更新 testkey 鍵值爲 Hello world。
$ etcdctl watch testkey
Hello world
支持的選項包括
- –forever 一直監測，直到用戶按 CTRL+C 退出
- –after-index ‘0’ 在指定 index 之前一直監測
- –recursive 返回所有的鍵值和子鍵值
exec-watch
監測一個鍵值的變化，一旦鍵值發生更新，就執行給定命令。
例如，用戶更新 testkey 鍵值。
$etcdctl exec-watch testkey – sh -c ‘ls’
default.etcd
Documentation
etcd
etcdctl
etcd-migrate
README-etcdctl.md
README.md
支持的選項包括
- –after-index ‘0’ 在指定 index 之前一直監測
- –recursive 返回所有的鍵值和子鍵值
集羣狀態
集羣狀態主要是etcdctl endpoint status 和etcdctl endpoint health兩條命令。
etcdctl --write-out=table --endpoints=$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
集羣成員
跟集羣成員相關的命令如下：
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列出集羣成員的命令。
etcdctl --endpoints=http://172.16.5.4:12379 member list -w table
+-----------------+---------+-------+------------------------+-----------------------------------------------+
| ID | STATUS | NAME | PEER ADDRS | CLIENT ADDRS |
+-----------------+---------+-------+------------------------+-----------------------------------------------+
| c856d92a82ba66a | started | etcd0 | http://172.16.5.4:2380 | http://172.16.5.4:2379,http://172.16.5.4:4001 |
+-----------------+---------+-------+------------------------+-----------------------------------------------+
————————————————