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I would like to setup my Ubuntu 12.04 LTS Server for a backdoor in case ssh crashes. I would simply connect to the server and restart ssh manually but this is not possible. Contacting the system administrator so he can restart it takes too much time aswell.

So is it possible to setup a web terminal to manage the system? If there are equal solutions i would be glad to know them. So far i have not found a web-terminal which is bound to ssh.

Thanks in advance.

Because of the negative downvotes i want to clarify:

We live in a dorm and the serverstructure is maintained by students. i don't have access to this structure and usually there are sometimes configuration problems (who knows what they do...). Openssh did in fact crash 2 times now and i couldn't find out why. 2 times the networkadmins were pissed about me saying i crashed it somehow eventhough they setup this serverinstance for me and i don't mess with the ssh settings (in fact i was not even working on the machine when the crash happened). That's why i needed a method to solve the hassle of waiting 2-3 month for the networkadmins to even look at my emails/case.


Thanks all. You are right, bypassing such security procedures is discouraged so i will have a look at monit to stabelize the system in a safe way.

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closed as off-topic by RobM, Sven, Ladadadada, pauska, Bryan Jun 28 '13 at 14:58

  • This question does not appear to be about server, networking, or related infrastructure administration within the scope defined in the help center.
If this question can be reworded to fit the rules in the help center, please edit the question.

This question appears to be off-topic because it is about bypassing security procedures put into place by operations staff. – RobM Jun 28 '13 at 10:42
have a look at the clarification – proxylittle Jun 28 '13 at 11:44
up vote 4 down vote accepted

OpenSSH usually doesn't crash. If you have a situation where this happens, investigate why as this is certainly not normal.

Alternatively, you could install a system like monit, which handles this automatically.

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This is the best way to fix this IMO, because SSHD should not crash unless something is the matter with the system. It can be an OOM problem or something else. Also, if your hw supports it you can get something like an iLO card to provide web based console access, because if you get a kernel panic or something then sshd will be unavailable to you. Also SSH is Secure shell, any other backdoor you'd want to install can provide a backdoor for malicious purposes too... – Petter H Jun 28 '13 at 10:44
sadly we can not install any hardware. but you are correct indeed ssh should not crash. 'monit' is a very good idea if it can provide automatic tasks i will have a look at it. – proxylittle Jun 28 '13 at 11:44

PHP Shell Terminal should do what you're looking for, check them out

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Having a way to manually go in to fix it is not a solution to rely on. You need to use a program like daemontools which will automatically restart a service it is killed. Better yet? Use none of these things and do nothing crazy on your server so SSH doesn't randomly die.

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setting up nginx to work with moinmoin wiki is not something that would be called 'crazy' i hope – proxylittle Jun 28 '13 at 11:46

While it's possible to setup a web terminal it's highly discouraged from a security perspective.

There are may different webshells around which allow for interactive command shell like PHPShell. Generally it's not a good idea to host one of these on your machine as these might be compromised by an attacker. So if you REALLY must implement it Iwould at least advice you to set restrictions which IPs are allowed to access the pages where your shell resides.

Personally I would recommend you to look into the following options if you REALLY need such functionality:

  • KVM over IP
  • ILO/DRAC (modules allowing remote hands directly implemented in the machine)

Note that preferably these are not directly connected to the internet, but only allowed from certain IP addresses or a VPN.

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actually this is the exact answer to my question. but i decided to accept the above answer as general solution for everyone with similar problems instead of a solution to do it the backdoor-way. Thank you. (i would upvote you but i don't have the needed rep) – proxylittle Jun 28 '13 at 12:03

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