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Chroot SSH trick: Difference between revisions

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Created page with "== chroot SSH Trick == This technique allows LabVIEW to run commands outside of its chroot on a LINX 3.0 (BBB or RPi2) target. This can be useful for interacting with commands..."
 
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This technique allows LabVIEW to run commands outside of its chroot on a LINX 3.0 (BBB or RPi2) target. This can be useful for interacting with commands that are unavailable inside the chroot like raspistill.
This technique allows LabVIEW to run commands outside of its chroot on a LINX 3.0 (BBB or RPi2) target. This can be useful for interacting with commands that are unavailable inside the chroot like raspistill.


# Install an ssh client to your chroot:
1. Install an ssh client to your chroot:
sudo schroot -r -c lv
sudo schroot -r -c lv
opkg update
opkg update
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exit
exit


# Configure pub key authentication so you don't have to type in a password interactively (Hint: This let's you use the ssh client from LabVIEW System Exec VI).
2. Configure pub key authentication so you don't have to type in a password interactively (Hint: This let's you use the ssh client from LabVIEW System Exec VI).
ssh-keygen -t rsa
ssh-keygen -t rsa
stick with the defaults when it prompts you, especially when it asks for the passphrase; we want an empty passphrase
stick with the defaults when it prompts you, especially when it asks for the passphrase; we want an empty passphrase
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sudo cp ~/.ssh/id_rsa* /srv/chroot/labview/root/.ssh/.
sudo cp ~/.ssh/id_rsa* /srv/chroot/labview/root/.ssh/.


# Now log back into the chroot and run the ssh command once so that you can add localhost to the list of known hosts
3. Now log back into the chroot and run the ssh command once so that you can add localhost to the list of known hosts
sudo schroot -r -c lv
sudo schroot -r -c lv
ssh root@localhost ls
ssh root@localhost ls
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exit
exit


#At this point you can run commands from within the LV chroot in the system outside the chroot by running a command of the form ssh <root_user>@localhost <command>. For instance, if I wanted to check the version of the Debian operation system on a Raspberry Pi I would run ssh pi@localhost cat /etc/debian_version. These commands can be run in a LabVIEW VI by using the System Exec VI, so now you have a way to execute commands outside of the LV chroot.
4. At this point you can run commands from within the LV chroot in the system outside the chroot by running a command of the form ssh <root_user>@localhost <command>. For instance, if I wanted to check the version of the Debian operation system on a Raspberry Pi I would run ssh pi@localhost cat /etc/debian_version. These commands can be run in a LabVIEW VI by using the System Exec VI, so now you have a way to execute commands outside of the LV chroot.

Revision as of 00:12, 8 July 2020

chroot SSH Trick

This technique allows LabVIEW to run commands outside of its chroot on a LINX 3.0 (BBB or RPi2) target. This can be useful for interacting with commands that are unavailable inside the chroot like raspistill.

1. Install an ssh client to your chroot: sudo schroot -r -c lv opkg update opkg install openssh-ssh exit

2. Configure pub key authentication so you don't have to type in a password interactively (Hint: This let's you use the ssh client from LabVIEW System Exec VI). ssh-keygen -t rsa stick with the defaults when it prompts you, especially when it asks for the passphrase; we want an empty passphrase cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys sudo mkdir /srv/chroot/labview/root/.ssh sudo cp ~/.ssh/id_rsa* /srv/chroot/labview/root/.ssh/.

3. Now log back into the chroot and run the ssh command once so that you can add localhost to the list of known hosts sudo schroot -r -c lv ssh root@localhost ls When prompted to add localhost to the list of known hosts, say yes exit

4. At this point you can run commands from within the LV chroot in the system outside the chroot by running a command of the form ssh <root_user>@localhost <command>. For instance, if I wanted to check the version of the Debian operation system on a Raspberry Pi I would run ssh pi@localhost cat /etc/debian_version. These commands can be run in a LabVIEW VI by using the System Exec VI, so now you have a way to execute commands outside of the LV chroot.