移除ticdc问题

[TiDBer_Y2d2kiJh]

【 TiDB 使用环境】生产环境 /测试/ Poc
【 TiDB 版本】v5.4.0 2tidb 3pd 3kv 1ticdc
【复现路径】ticdc服务器的数据目录被弄坏了，估计数据都要被删除才能恢复这个存储的挂载，现在这个ticdc的状态是down，现在的问题是我还能通过缩容的方式来进行ticdc卸载吗？或者有没有更优的方式来处理这个ticdc组件。
【遇到的问题：问题现象及影响】
【资源配置】
【附件：截图/日志/监控】

[songxuecheng (小白)]

1个cdc 只能缩容在扩容了，数据要看你自己的恢复了，下游容忍重复的话，可以到指定时间开始

[TiDBer_嘎嘣脆 (Ti D Ber 3et Iux Gi)]

如果两个集群在同步cdc，可以将cdc部署到另一个集群中，A集群中down掉的cdc已经在pd中信息状态是down，所以将B集群注册新的cdc到A集群的pd中不影响的

[ffeenn (ThatBoy)]

强制缩容，然后再扩容，最快的方法。

[TiDBer_Y2d2kiJh]

下游还没有开始同步数据

[songxuecheng (小白)]

缩容在扩容即可

[zhanggame1 (Ti D Ber G I13ecx U)]

当然是缩容最简单了

[redgame (Ti D Ber Pa Amoi Ul)]

可以缩容再扩容

[TiDBer_Y2d2kiJh]

因为没有操作过，不知道这种情况下能不能操作成功。

[zhanggame1 (Ti D Ber G I13ecx U)]

可以装个测试机先试试，并不复杂，单机部署就行
文件没有了删除可以加–force 参数

[zhanggame1 (Ti D Ber G I13ecx U)]

我在7.1.0上单机测了下：
先扩容加了个cdc节点

root@tidb:~# tiup cluster scale-out tidb-test scale-out-cdc.yml -u root -p
tiup is checking updates for component cluster ...
Starting component `cluster`: /root/.tiup/components/cluster/v1.12.5/tiup-cluster scale-out tidb-test scale-out-cdc.yml -u root -p
Input SSH password:

+ Detect CPU Arch Name
  - Detecting node 127.0.1.1 Arch info ... Done

+ Detect CPU OS Name
  - Detecting node 127.0.1.1 OS info ... Done
Please confirm your topology:
Cluster type:    tidb
Cluster name:    tidb-test
Cluster version: v7.1.0
Role  Host       Ports  OS/Arch       Directories
----  ----       -----  -------       -----------
cdc   127.0.1.1  8300   linux/x86_64  /tidb-deploy/cdc-8300,/tidb-data/cdc-8300
Attention:
    1. If the topology is not what you expected, check your yaml file.
    2. Please confirm there is no port/directory conflicts in same host.
Do you want to continue? [y/N]: (default=N) y
+ [ Serial ] - SSHKeySet: privateKey=/root/.tiup/storage/cluster/clusters/tidb-test/ssh/id_rsa, publicKey=/root/.tiup/storage/cluster/clusters/tidb-test/ssh/id_rsa.pub
+ [Parallel] - UserSSH: user=tidb, host=127.0.1.1
+ [Parallel] - UserSSH: user=tidb, host=127.0.1.1
+ [Parallel] - UserSSH: user=tidb, host=127.0.1.1
+ [Parallel] - UserSSH: user=tidb, host=127.0.1.1
+ [Parallel] - UserSSH: user=tidb, host=127.0.1.1
+ Download TiDB components
  - Download cdc:v7.1.0 (linux/amd64) ... Done
+ Initialize target host environments
+ Deploy TiDB instance
  - Deploy instance cdc -> 127.0.1.1:8300 ... Done
+ Copy certificate to remote host
+ Generate scale-out config
  - Generate scale-out config cdc -> 127.0.1.1:8300 ... Done
+ Init monitor config
Enabling component cdc
        Enabling instance 127.0.1.1:8300
        Enable instance 127.0.1.1:8300 success
Enabling component node_exporter
        Enabling instance 127.0.1.1
        Enable 127.0.1.1 success
Enabling component blackbox_exporter
        Enabling instance 127.0.1.1
        Enable 127.0.1.1 success
+ [ Serial ] - Save meta
+ [ Serial ] - Start new instances
Starting component cdc
        Starting instance 127.0.1.1:8300
        Start instance 127.0.1.1:8300 success
Starting component node_exporter
        Starting instance 127.0.1.1
        Start 127.0.1.1 success
Starting component blackbox_exporter
        Starting instance 127.0.1.1
        Start 127.0.1.1 success
+ Refresh components conifgs
  - Generate config pd -> 127.0.1.1:2379 ... Done
  - Generate config tikv -> 127.0.1.1:20160 ... Done
  - Generate config tidb -> 127.0.1.1:4000 ... Done
  - Generate config cdc -> 127.0.1.1:8300 ... Done
  - Generate config prometheus -> 127.0.1.1:9090 ... Done
  - Generate config grafana -> 127.0.1.1:3000 ... Done
+ Reload prometheus and grafana
  - Reload prometheus -> 127.0.1.1:9090 ... Done
  - Reload grafana -> 127.0.1.1:3000 ... Done
+ [ Serial ] - UpdateTopology: cluster=tidb-test
Scaled cluster `tidb-test` out successfully

然后模拟cdc节点损坏，rm删除了cdc
rm -rf /tidb-deploy/cdc-8300
rm -rf /tidb-data/cdc-8300
重启了集群，看到cdc离线了

然后tiup cluster scale-in tidb-test --node 127.0.1.1:8300删除成功，不成功可以加–force 参数

[TiDBer_Y2d2kiJh]

NB!