etcd租約機制

新建租約

新建一個過時時間爲120s的租約

# etcdctl lease grant 120
lease 018f6d7bb11aba0d granted with TTL(120s)

查看新建的租約信息

# etcdctl lease list
found 1 leases
018f6d7bb11aba0d

  # etcdctl lease timetolive 018f6d7bb11aba0d --keys
  lease 018f6d7bb11aba0d granted with TTL(120s), remaining(99s), attached keys([])

新建key，併爲該key指定租約

# etcdctl put name alice --lease="018f6d7bb11aba0d"
OK
# etcdctl put name1 tina --lease="018f6d7bb11aba0d"
OK

# etcdctl lease timetolive 018f6d7bb11aba0d --keys

lease 018f6d7bb11aba0d granted with TTL(120s), remaining(60s), attached keys([name name1])

  # etcdctl get --prefix ""
  name
  alice
  name1
  tina

等到租約過時後，再次查看租約已通過期，對應的key也已經被自動刪除

# etcdctl lease timetolive 018f6d7bb11aba0d --keys
lease 018f6d7bb11aba0d already expired

 續約

新建租約並賦予key值

# etcdctl lease grant 30
lease 018f6d7bd032c117 granted with TTL(30s)
# etcdctl put name alice --lease=018f6d7bd032c117
OK

 在租約即將過時時進行續約，命令不會自動結束，會一直顯示該窗口

# etcdctl lease keep-alive 018f6d7bd032c117
lease 018f6d7bd032c117 keepalived with TTL(30)
lease 018f6d7bd032c117 keepalived with TTL(30)
lease 018f6d7bd032c117 keepalived with TTL(30)
......

 從新打開一個窗口，查看該租約續約信息，能夠看到該租約會自動續約，相應key值也不會被刪除

# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(23s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(22s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(21s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(20s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(29s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(28s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(27s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(27s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(26s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(25s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(25s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(24s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(23s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(22s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(22s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(20s), attached keys([name])
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 granted with TTL(30s), remaining(29s), attached keys([name])

回收租約 

回收租約會自動刪除與該租約關聯的key

# etcdctl lease revoke 018f6d7bd032c117
lease 018f6d7bd032c117 revoked
# etcdctl lease timetolive 018f6d7bd032c117 --keys
lease 018f6d7bd032c117 already expired
# etcdctl get name