Setup an Ubuntu VM as SFTP Server for NSX-T backup

In this blog, I will be setting up an Ubuntu Virtual Machine  as a SFTP Server for NSX-T config backups.

• Set an Ubuntu Server , I used the below release

animeshd@sftp:~$ lsb_release -a

Distributor ID: Ubuntu
Description: Ubuntu 18.04 LTS
Release: 18.04
Codename: bionic

• Installed VMware tools on the Ubuntu machine.
• Install latest updates to the Ubuntu Machine using : sudo apt-get update (assume internet access is there)
• Next , Install an Openssh Server using : sudo apt install openssh-server

check the status of ssh – running

Next, using putty ssh to the server, and take the backup of /etc/ssh/sshd_config file.

In the current example, I took a backup of the file under the tmp directory as /tmp/sshd_backup.

As the original file is read only, use chmod 777 against the /etc/ssh/sshd_config file to edit it. Use an editor of your choice on the system, I used Nano editor to the open the file for editing.

• Edit the ListenIPaddress and add the IP of the local machine.

• Then change X11Forwarding no   (change from ‘yes’), and then add the overriding settings as per the screenshot below.

Here’s what each of those directives do:

• Match User tells the SSH server to apply the following commands only to the user specified.
• ForceCommand internal-sftp forces the SSH server to run the SFTP server upon login.
• PasswordAuthentication yes allows password authentication for this user.
• ChrootDirectory /var/nsxtsftp/ ensures that the user will not be allowed access to anything beyond the /var/nsxtsftp directory.
• AllowAgentForwarding no, AllowTcpForwarding no. and X11Forwarding no disables port forwarding, tunneling and X11 forwarding for this user.

Restart the ssh service on the machine

• Now, I have created these directory and user in the on the SFTP Ubuntu machine.

Create a new user

• sudo adduser –shell /bin/false nsxtbackupuser

Create a new directory

• sudo mkdir -p /var/nsxtsftp/backups

Change owner and  permission on the new directory

• sudo chown root:root /var/nsxtsftp
• sudo chown nsxtbackupuser:nsxtbackupuser /var/nsxtsftp
• sudo chown 755 /var/nsxtsftp

Once, this is done use the NSX-T UI, under system go ahead and edit and configure backup to the backup server.

Then, perform a backup and view the result.

Backup files are getting created.