# [Known-Issues]TiKV panic,reported fatal error like No such file or directory

## Kew Words

TiKV panic, Result::unwrap(), No such file or directory,

## Description

TiKV 节点 panic 之后无法启动，查看 tikv.log 日志中有 FATAL 信息：

```golang
[2021/04/21 18:21:21.783 +08:00] [FATAL] [lib.rs:465] ["called `Result::unwrap()` on an `Err` value: Os { code: 2, kind: NotFound, message: \"No such file or directory\" }"] [backtrace="stack backtrace:\n   0: tikv_util::set_panic_hook::{{closure}}\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v5.0.0/tikv/components/tikv_util/src/lib.rs:464\n   1: std::panicking::rust_panic_with_hook\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35//library/std/src/panicking.rs:595\n   2: std::panicking::begin_panic_handler::{{closure}}\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35//library/std/src/panicking.rs:497\n   3: std::sys_common::backtrace::__rust_end_short_backtrace\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35//library/std/src/sys_common/backtrace.rs:141\n   4: rust_begin_unwind\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35//library/std/src/panicking.rs:493\n   5: core::panicking::panic_fmt\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35//library/core/src/panicking.rs:92\n   6: core::option::expect_none_failed\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35//library/core/src/option.rs:1266\n   7: core::result::Result<T,E>::unwrap\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35/library/core/src/result.rs:969\n      cmd::server::TiKVServer<ER>::init_fs\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v5.0.0/tikv/cmd/src/server.rs:378\n      cmd::server::run_tikv\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v5.0.0/tikv/cmd/src/server.rs:138\n   8: tikv_server::main\n             at /home/jenkins/agent/workspace/build_tikv_multi_branch_v5.0.0/tikv/cmd/src/bin/tikv-server.rs:181\n   9: core::ops::function::FnOnce::call_once\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35/library/core/src/ops/function.rs:227\n      std::sys_common::backtrace::__rust_begin_short_backtrace\n             at /rustc/bc39d4d9c514e5fdb40a5782e6ca08924f979c35/library/std/src/sys_common/backtrace.rs:125\n  10: main\n  11: __libc_start_main\n  12: <unknown>\n"] [location=cmd/src/server.rs:393] [thread_name=main]
```

## Root Cause

文件系统损坏，导致 space_holder 文件创建出来了，但是在分配空间的时候失败。

## Diagnostic Steps

根据报错信息 [location=cmd/src/server.rs:393] 查看对应版本代码位置：<https://github.com/tikv/tikv/blob/v5.0.0/cmd/src/server.rs#L393>

定位是在创建 tikv space_holder 文件的时候创建失败，发生了 panic 的情况。

排查：

1. 服务器剩余磁盘空间是否足够
2. 文件及目录权限是否正确
3. 文件系统是否正常

## Resolution

修复文件系统

## Workaround

N/A