我的 VPS 上的 TCP 连接存在一些问题。有时，达到了服务器上允许的最大连接数，并且 ssh 连接被拒绝。我有一些设备通过反向 ssh 隧道连接到服务器，我不知道我是否正确管理这些连接。
在下面的示例中，我显示了仅由 4 个通过反向 ssh 隧道连接的设备创建的连接。
[root@vps-pruebas ~]# netstat -naptu | grep fichar
tcp 0 0 127.0.0.1:4404 0.0.0.0:* LISTEN 11988/sshd: ficharc
tcp 0 0 127.0.0.1:4401 0.0.0.0:* LISTEN 9896/sshd: ficharce
tcp 0 0 127.0.0.1:4402 0.0.0.0:* LISTEN 11981/sshd: ficharc
tcp 0 0 127.0.0.1:4403 0.0.0.0:* LISTEN 9887/sshd: ficharce
tcp 0 0 38.59.113.62:22 81.32.245.105:44780 ESTABLISHED 12386/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44778 ESTABLISHED 12347/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44758 ESTABLISHED 12179/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44736 ESTABLISHED 12011/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44754 ESTABLISHED 12149/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44768 ESTABLISHED 12253/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44776 ESTABLISHED 12345/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44788 ESTABLISHED 12436/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44742 ESTABLISHED 12044/sshd: ficharc
tcp 0 0 38.59.113.62:22 203.0.68.60:12737 ESTABLISHED 9885/sshd: ficharce
tcp 0 0 38.59.113.62:22 81.32.245.105:44760 ESTABLISHED 12183/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44770 ESTABLISHED 12282/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44740 ESTABLISHED 12020/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44732 ESTABLISHED 11979/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44786 ESTABLISHED 12427/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44762 ESTABLISHED 12185/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44752 ESTABLISHED 12147/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44790 ESTABLISHED 12468/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.28.223.129:54650 ESTABLISHED 11986/sshd: ficharc
tcp 0 0 38.59.113.62:22 81.32.245.105:44744 ESTABLISHED 12056/sshd: ficharc
tcp 0 0 38.59.113.62:22 203.0.68.60:47486 ESTABLISHED 9894/sshd: ficharce
tcp 0 0 38.59.113.62:22 81.32.245.105:44756 ESTABLISHED 12161/sshd: ficharc
tcp6 0 0 ::1:4404 :::* LISTEN 11988/sshd: ficharc
tcp6 0 0 ::1:4401 :::* LISTEN 9896/sshd: ficharce
tcp6 0 0 ::1:4402 :::* LISTEN 11981/sshd: ficharc
tcp6 0 0 ::1:4403 :::* LISTEN 9887/sshd: ficharce
通过 ssh 连接的 4 个设备产生如此多的活动连接，这正常吗？
编辑以添加所需的信息。我在每个设备上打开了反向隧道，只是为了在需要检查任何内容时连接到它们。但是，通过 Cron 任务，设备连接到 VPS 以检查更新并将一些文件放入服务器