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tuxEvangelist's avatar
Dec 06, 2021
Solved

EnableSSH - Locked out from SSH

Dear All,

I've installed EnableSSH on my Duo v2 successfully and was able to use it with the root account. While trying to enable ssh access to other users, I unfortunately locked root out before managing to enable another user.

 

Right now the successful login with a non-root user leads to an instant logout.

Loggin in with root leads to "Permisson denied, please try again". The reason for this is probably a wrong entry in the "Allowed Users" section of the ssh configuration.

 

Normal admin access via the Web UI is not affected and runs perfectly well.

 

I've already tried re-installing the EnableSSH plugin, but unfortunately that did not reset the ssh configuration.

 

Is there any way to reset only the ssh config without possibly running into problems on the Web UI side?

  • StephenB's avatar
    StephenB
    Dec 07, 2021

    tuxEvangelist wrote:

     

    Thanks for the quick reply, I managed to get into tech support mode and telnet to the Duo v2, but unfortunately the files of the ssh configuration are not present in this state. Is there a chance that I can mount other parts of the filesystem that contain the config files of the plugins that are installed?

     


    Yes, you need to mount the real OS partition.

     

    I've never owned a v2. but I believe these commands will work/

    # start_raid.sh
    # mount /dev/md0 /sysroot

    Not sure if you'll also need to chroot to get the commmands you need, but if you do try these commands:

    # mount --bind /proc /sysroot/proc
    # mount --bind /dev /sysroot/dev
    # mount --bind /dev/pts /sysroot/dev/pts
    # mount --bind /sys /sysroot/sys
    # chroot /sysroot /bin/bash

8 Replies

Replies have been turned off for this discussion
  • StephenB's avatar
    StephenB
    Guru - Experienced User

    tuxEvangelist wrote:

     

    Is there any way to reset only the ssh config without possibly running into problems on the Web UI side?


    You can get into the OS using tech support mode.  You'd be on your own after that though.

    • tuxEvangelist's avatar
      tuxEvangelist
      Aspirant

      D

      Is there any way to reset only the ssh config without possibly running into problems on the Web UI side?

      > You can get into the OS using tech support mode.  You'd be on your own after that though.

       

      Thanks for the quick reply, I managed to get into tech support mode and telnet to the Duo v2, but unfortunately the files of the ssh configuration are not present in this state. Is there a chance that I can mount other parts of the filesystem that contain the config files of the plugins that are installed?

       

      And, BTW what is the way to gracefully shutdown the system from tech support mode? Pulling the plug is the only way I've found and that really hurts me every time :-o

       

      • StephenB's avatar
        StephenB
        Guru - Experienced User

        tuxEvangelist wrote:

         

        Thanks for the quick reply, I managed to get into tech support mode and telnet to the Duo v2, but unfortunately the files of the ssh configuration are not present in this state. Is there a chance that I can mount other parts of the filesystem that contain the config files of the plugins that are installed?

         


        Yes, you need to mount the real OS partition.

         

        I've never owned a v2. but I believe these commands will work/

        # start_raid.sh
        # mount /dev/md0 /sysroot

        Not sure if you'll also need to chroot to get the commmands you need, but if you do try these commands:

        # mount --bind /proc /sysroot/proc
        # mount --bind /dev /sysroot/dev
        # mount --bind /dev/pts /sysroot/dev/pts
        # mount --bind /sys /sysroot/sys
        # chroot /sysroot /bin/bash
  • Sandshark's avatar
    Sandshark
    Sensei - Experienced User

    Do a configuration backup (under Settings/System/Backup) and see if the file you need to fix is in it.  If it is, be sure to use an editor that will use an LF only for an EoL and not add anything (Like Notepad++) and make the changes you need to, then restore that backup.

    • tuxEvangelist's avatar
      tuxEvangelist
      Aspirant

      > Do a configuration backup (under Settings/System/Backup) and see if the file you need to fix is in it. If it is, be sure to use an editor that will use an LF only for an EoL and not add anything (Like Notepad++) and make the changes you need to, then restore that backup.

       

      Thanks for the quick reply - I've checked that already with older config backups, but unfortunately the file I'm looking for is not contained there - even if I'm doing a present config backup with "All" option marked.

       

      The crucial file is

       

      sshd_config

      and it's supposed to sit somewhere like

      /etc/ssh

       

      • Sandshark's avatar
        Sandshark
        Sensei - Experienced User

        tuxEvangelist wrote:

         

        Thanks for the quick reply - I've checked that already with older config backups, but unfortunately the file I'm looking for is not contained there - even if I'm doing a present config backup with "All" option marked.

         

        The crucial file is

         

        sshd_config

        and it's supposed to sit somewhere like

        /etc/ssh

         


        If support mode doesn't get you there, I suppose you could try just putting it into the config backup .zip and see if the restore really checks and restores specific content or restores whatever it finds.  I know you can delete files from the .zip to be restored with no issue, I've never tried to add any.

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