Glad my instructions were helpful. I tried really hard to make the instructions as useful as possible to reach more people. There are certainly more complexities that I could have included to do more customization but that then becomes more information to digest.
I think you are going about it the right way to not just follow the steps but to try and understand what the purpose of each step is. When you understand the "why" of each step then allows you to make changes to suit your needs. Certainly moving the Cumulus MX folder to a different location is possible, as you are wanting to do and have it on an SSD.
But before I get into discussing the particulars of moving to an SSD you should know that it is now possible to set up a Pi that boots from SSD and doesn't have an SD card. Certainly if you go about it this way then there is no need to make any modifications as everything is on the SSD. So this is but one solution.
Yes, you are correct that steps 4, 5, and 6 would need to be modified to reference the SSD location. But not necessarily if you mount the SSD so that the mount point is in your home folder or you mount to /mnt and then create a symbolic link. Linux allows you to mount a drive or a directory in another drive anywhere you want. If you do it this way then /home/username/CumulusMX can be an SSD location while /home/username is on the SD card. If done in this manner then no modification of steps 4, 5, and 6 are required.
Regarding the mounting of the SSD, the RPI OS will automatically do an auto-mount, and present the drive under /media/pi/<hard-drive-label> and although that can be helpful to a novice user it is not going to work for launching Cumulus MX as a service if the CumulusMX folder is off on a hard drive that is being auto-mounted...because it only mounts when you log in. Therefore it is necessary to use fstab to permanently mount the hard drive. The typical location to mount a hard drive is /mnt and then if you wanted you could have a symbolic link to CumulusMX on the SSD over to /home/username/CumulusMX. Or if you prefer to not do the symbolic link then you could just change the reference path in steps 4, 5, and 6. Here are some simple instructions on working with fstab an the Pi. You should read some other write-ups on using fstab to understand it better...or not...up to you:
https://www.raspberrypi.org/documentati ... storage.md
So there you have it ....two solutions to move the CumulusMX folder to a hard drive (mounting or direct OS install with no SD card)
I do recommend that if you are mounting an external drive that it be formatted as ext4. Even though Linux can read/write to NTFS and other partition types, it is going to perform better and be better protected by the journaling functions of ext4 (better suited for power loss), less chance of file corruption, faster read/write performance, and you'll be able to use Linux file system permissions, and there are some other benefits.
To move your your existing Cumulus MX install over to the Pi you should just treat it like you would any other upgrade that you do to Cumulus MX. Just start with your old CumulusMX folder and then (after making a backup) copy over the new unzipped version...and then if required bring over any customizations you have done if any.
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