TiKV Service Deployment: Specifying data_dir for Each Instance, Multi-Disk Deployment, How Are Failure Domains Divided?

Note:
This topic has been translated from a Chinese forum by GPT and might contain errors.

Original topic: TiKV服务部署 每个实例指定data_dir 多盘部署 故障域是怎么划分?

| username: TiDBer_r2nJcto0

[TiDB Usage Environment] Testing
[TiDB Version] 7.5
[Reproduction Path] Use TiUP to set data_dir to multiple filesystem paths, such as: /data1, /data2, /data3, /data4
[Encountered Issue: If disk data1 is damaged but data2-4 are normal, will this TiKV instance be marked as faulty?]
[Resource Configuration] Enter TiDB Dashboard - Cluster Info - Hosts and take a screenshot of this page
[Attachment: Screenshot/Logs/Monitoring]

| username: 像风一样的男子 | Original post link

It seems that only TiFlash supports configuring multiple directories in data_dir, while TiKV does not.

| username: DBAER | Original post link

Marking it, haven’t used it this way before. Is this for hot and cold data separation?

| username: 小龙虾爱大龙虾 | Original post link

A single TiKV instance does not support multiple data_dirs.

| username: chenhanneu | Original post link

Each directory for one TiKV or one TiKV using multiple disks in a RAID configuration.

| username: TiDBer_QYr0vohO | Original post link

Can it be played like this? It feels a bit like RAID.

| username: 这里介绍不了我 | Original post link

Can this thing be made into a RAID? Looking forward to it.

| username: 扬仔_tidb | Original post link

I also encountered this problem. Using a cloud host, a single disk has an IO limit. I also want to deploy multiple disks, but there is no solution yet.

| username: zhh_912 | Original post link

TiKV does not support fault domains.

| username: yytest | Original post link

TiKV indeed does not support multiple data_dirs.

| username: tidb菜鸟一只 | Original post link

TiKV does not support configuring multiple directories for a single node; only TiFlash supports this.

| username: 呢莫不爱吃鱼 | Original post link

Only TiFlash supports it; TiKV does not support fault domains.

| username: kkpeter | Original post link

TiKV does not support this, right?

| username: 洪七表哥 | Original post link

Tikv does not support configuring multiple directories for a single node.

| username: 柴米油酱 | Original post link

TiKV does not support it unless you configure your disk with RAID.

| username: 友利奈绪 | Original post link

TiKV is not supported.

| username: TiDBer_r2nJcto0 | Original post link

You can use LVM striped volumes to achieve multi-disk acceleration for your issue.

| username: TiDBer_r2nJcto0 | Original post link

Thank you all for your answers. During the experiment, I found the answer: the data_dir of TiKV does not support configuring multiple disk paths.
My current situation is deploying TiKV on two physical machines (with 3 data disks each) and planning how to utilize the disks.

The current solution is:
Deploy the corresponding TiKV instances on each physical machine according to the number of disks and bind a single disk to each instance.
Then use the labeling feature to divide fault domains.
As @zhh_912 mentioned, there is no concept of fault domains, but the labeling feature can be used to achieve the functionality of fault domains.

Schedule Replicas by Topology Labels | PingCAP Documentation Center

| username: 托马斯滑板鞋 | Original post link

This is a bit frustrating. After using Doris for a while, I’ve gotten used to attaching as many disks as possible on bare metal to improve IO. :joy:

| username: 小于同学 | Original post link

Not supported