尝试建立远程 ssh 端口转发:
在我的远程主机上,/etc/ssh/sshd_config
客户端指定的 GatewayPorts
在我的本地计算机上:
ssh -g -R 1234:0.0.0.0:8000 me@my-remote-host
通过调试,我们可以读取:
debug1: Authentication succeeded (publickey).
Authenticated to s1.bux.fr ([178.32.223.76]:22).
debug1: Remote connections from LOCALHOST:1234 forwarded to local address 0.0.0.0:8000
debug2: fd 3 setting TCP_NODELAY
debug1: Requesting [email protected]
debug1: Entering interactive session.
debug1: remote forward success for: listen 1234, connect 0.0.0.0:8000
debug1: All remote forwarding requests processed
在远程主机上,我们可以联系1234端口(WSGIServer/0.2 CPython/3.4.3
是本地机器的8000端口):
# http :1234
HTTP/1.0 302 Found
Content-Type: text/html; charset=utf-8
Date: Wed, 19 Oct 2016 13:26:00 GMT
Location: /accounts/login/
Server: WSGIServer/0.2 CPython/3.4.3
Vary: Cookie
X-Frame-Options: SAMEORIGIN
我们可以查看开放的端口:
# netstat -tupln | grep 1234
tcp 0 0 127.0.0.1:1234 0.0.0.0:* LISTEN 14460/1
tcp6 0 0 ::1:1234 :::* LISTEN 14460/1
但是,从世界上的另一台机器,我无法联系my-remote-host:1324
:
# http my-remote-host:1234
http: error: ConnectionError: HTTPConnectionPool(host='my-remote-host', port=1234): Max retries exceeded with url: / (Caused by NewConnectionError('<requests.packages.urllib3.connection.HTTPConnection object at 0xb6b2fbec>: Failed to establish a new connection: [Errno 111] Connection refused',)) while doing GET request to URL: http://my-remote-host:1234/
我的远程主机上没有防火墙:
# iptables -L
[sudo] password for bux:
Chain INPUT (policy ACCEPT)
target prot opt source destination
fail2ban-sshd tcp -- anywhere anywhere multiport dports ssh
fail2ban-ssh tcp -- anywhere anywhere multiport dports ssh
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain fail2ban-ssh (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain fail2ban-sshd (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
如何找到阻塞的地方?
答案1
tcp 0 0 127.0.0.1:1234 0.0.0.0:* LISTEN 14460/1
在 netstat 的输出中可以清楚地看到问题。您的远程计算机正在监听 127.0.0.1:1234,该地址仅适用于该计算机的本地连接。
为了使 ssh -g(网关选项)正常工作,您必须指定通配符地址或一些可从外部客户端访问的接口地址,例如:
ssh -g -R 0.0.0.0:1234:0.0.0.0:8000 me@my-remote-host
答案2
找到的解决方案是https://superuser.com/questions/588591/how-to-make-ssh-tunnel-open-to-public:
我们必须像这样设置绑定地址:
ssh -R 0.0.0.0:1234:0.0.0.0:8000 me@my-remote-host
答案3
从man ssh
:
-g Allows remote hosts to connect to local forwarded ports. If used on a multiplexed connection, then this option must be specified on the master process.
-L
为了当地的-R
转发,以及偏僻的转发。-g
不适用于远程。