[GH-ISSUE #3796] 使用tcpmux时 customDomains 参数大写导致 kex_exchange_identification connection closed by remote host

gitea-mirror commented

2026-05-05 13:57:10 -06:00

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Originally created by @GokouRuri1996 on GitHub (Nov 23, 2023).
Original GitHub issue: https://github.com/fatedier/frp/issues/3796

Bug Description

我使用ubuntu 20.04 作为服务器和客户端。在配置 customDomains 参数时，我发现其中含有大写字母会导致使用ssh 连接时报错。
报错信息：
2023/XX/XX XXXXXX socat[5317] E CONNECT XXXXX: Not Found
ssh_exchange_identification: Connection closed by remote host

在删去参数中所有的大写字母，问题不再出现。
如果你也遇到同样的问题，可以尝试一下。

frpc Version

0.52.3

frps Version

0.52.3

System Architecture

linux/amd64

Configurations

serverAddr = "x.x.x.x"
serverPort = 7000

proxies
name = "ssh1"
type = "tcpmux"
multiplexer = "httpconnect"
customDomains = ["machine-a.example.com"] //这里的参数含有大写字母会出现问题
localIP = "127.0.0.1"
localPort = 22

Logs

No response

Steps to reproduce

...

Affected area

Docs
Installation
Performance and Scalability
Security
User Experience
Test and Release
Developer Infrastructure
Client Plugin
Server Plugin
Extensions
Others

Originally created by @GokouRuri1996 on GitHub (Nov 23, 2023). Original GitHub issue: https://github.com/fatedier/frp/issues/3796 ### Bug Description 我使用ubuntu 20.04 作为服务器和客户端。在配置 customDomains 参数时，我发现其中含有大写字母会导致使用ssh 连接时报错。报错信息： 2023/XX/XX XXXXXX socat[5317] E CONNECT XXXXX: Not Found ssh_exchange_identification: Connection closed by remote host 在删去参数中所有的大写字母，问题不再出现。如果你也遇到同样的问题，可以尝试一下。 ### frpc Version 0.52.3 ### frps Version 0.52.3 ### System Architecture linux/amd64 ### Configurations serverAddr = "x.x.x.x" serverPort = 7000 [[proxies]] name = "ssh1" type = "tcpmux" multiplexer = "httpconnect" customDomains = ["machine-a.example.com"] //这里的参数含有大写字母会出现问题 localIP = "127.0.0.1" localPort = 22 ### Logs _No response_ ### Steps to reproduce 1. 2. 3. ... ### Affected area - [ ] Docs - [ ] Installation - [ ] Performance and Scalability - [ ] Security - [X] User Experience - [ ] Test and Release - [ ] Developer Infrastructure - [ ] Client Plugin - [ ] Server Plugin - [ ] Extensions - [ ] Others

gitea-mirror

2026-05-05 13:57:11 -06:00

closed this issue
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gitea-mirror commented

2026-05-05 13:57:13 -06:00

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@fatedier commented on GitHub (Nov 23, 2023):

一般对于 host 来说，可能可以考虑代码中忽略大小写

@fatedier commented on GitHub (Nov 23, 2023): 一般对于 host 来说，可能可以考虑代码中忽略大小写

gitea-mirror commented

2026-05-05 13:57:14 -06:00

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@johngai19 commented on GitHub (Dec 22, 2023):

请教一下，这里的"machine-a.example.com"]是要真实存在的域名，还是可以随便写，如果要真实存在的，那么域名解析应该怎么设置，谢谢您。我按照教程示例使用ssh复用同一个端口始终不成功，不知道问题出在哪个环节。

@johngai19 commented on GitHub (Dec 22, 2023): 请教一下，这里的"machine-a.example.com"]是要真实存在的域名，还是可以随便写，如果要真实存在的，那么域名解析应该怎么设置，谢谢您。我按照教程示例使用ssh复用同一个端口始终不成功，不知道问题出在哪个环节。

gitea-mirror commented

2026-05-05 13:57:15 -06:00

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@nicksuslov commented on GitHub (Jan 29, 2024):

any updates on this? have same problem

@nicksuslov commented on GitHub (Jan 29, 2024): any updates on this? have same problem

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