Prerequisites for adding the Linux Host to OmniDeq for discovery


Resource CPU RAM /home/ /opt
Requirement 4 cores 8 GB > 500 MB > 2 GB

Discovery uses /opt partition for its operation. Please allow the executable permissions to the folder. Verify it as follows on the Host.

[ssh-user@host ~]$ ls -ltr /opt
drwxr-xr-x  9 root  testdir  288 Sep 27  2016 X11   

"x" is required which ensures the execute permission.

Privilege Access

The user account used for connection between OmniDeq and host must have privilege access.

Below line can be added to /etc/sudoers for allowing connecting user to communicate without password certain commands. Please update the path for system commands like mkdir, echo etc

<ssh-user-for-omnideq-host> ALL=(ALL) NOPASSWD:/opt/.ch-tools/*/*/*, /opt/.ch-tools/*/*, /bin/mkdir, /bin/echo, /bin/chmod 755 /opt/.ch-tools/*, /bin/chmod 755 /home/<ssh-user-for-omnideq-host>/chcmd, /bin/chmod -R 755 /opt/.ch-tools, /bin/chmod -R 755 /home/<ssh-user-for-omnideq-host>/.ch-tools, /bin/chown <ssh-user-for-omnideq-host>\: /opt/.ch-tools/*, /bin/chown -R <ssh-user-for-omnideq-host>\: /home/<ssh-user-for-omnideq-host>/chcmd, /bin/chown -R <ssh-user-for-omnideq-host>\: /opt/.ch-tools, /bin/chown -R <ssh-user-for-omnideq-host>\: /home/<ssh-user-for-omnideq-host>/.ch-tools

RequireTTY

Disable requiretty for connecting user from remote machine to Host. If set, sudo will only run when the user is logged in to a real terminal and not via other means such as cron, cgi-bin or ssh scripts. Since OmniDeq connects to the Host remotely without a real terminal, this flag must be disabled. This flag is off by default. Below line can be added to /etc/sudoers file. 

Defaults:<ssh-user-for-omnideq-host>    !requiretty

SSHD server

The ssh server (sshd) must be running on the host. Verify it as follows on the Host.

[ssh-user@host ~]$ ps ax | grep <sshd or openssh or equivalent>

Connection between Host and OmniDeq

OmniDeq authenticates with the Linux Host using the following 2 methods over ssh

Host communicates back to OmniDeq over port 443 ( https ). Please ensure that port 443 is enabled on the Host for external communication and unblocked on the firewall in between Host and OmniDeq.