Dual boot Ubuntu 16.04 and 20.04

I have dual boot on my machine with 1 Tb HDD I left 16.04 on my machine when I updated to 18.04 just in case 18.04 wasn’t for me and now I am running 20.04. I would like to remove the 16.04 and resize my partitions. I have done this in the past. I was biting my nails the whole time but it worked. That was back in the Jaunty Jackalope 9.04 days removing Window$. I used Gparted and still do but I am very nervous. I use Timeshift to backup my HDD. Is there anything I should be aware of before I attempt this? Sorry if this is the wrong place to ask this question but, can you help me? Thanks in advance.

It should work just fine, but if you don’t know exactly what you’re doing, your boot manager might get confused if you resize the existing partitions.

My approach would rather be: Backup all my data and to do a fresh installation over the entire disk.

Thank you Mina,
Like I stated earlier I have done it before but years ago. If I do a back up of all my data would I be able to fit it onto a DVD-R or would you recommend a thumb drive? Biggest I have currently is 128 Gb. Now by data you mean what exactly, I have my documents backed up via Dropbox, Mega and Google Drive (can’t have to many). I’m really not clear on ‘data’. Would that be the OS settings and software settings, Web Browser, Thunderbird etc. Just to mention a few.

Just backup everything that is important to you. Whether it is documents or programs, it’s better to backup a little more than too little.


As @Mina and @Akito mentioned above, first BACKUP all your stuff!
Since Déjà-dup and TimeShift are available for both 16.04 and 20.04, you could create a Backup using any of these tools. Might be 128GB from your thumb drive + 50GB from Mega is enough for you. DéjàDup can sync your data using Drive, Dropbox, Nextcloud, Syncthing, or any cloud solution you have.

As you mention, your stuff is not limited to your documents/images/videos, but Thunderbird contacts, Browser favorites, Data Bases from other programs such as phone Backups (I’m using Syncthing in order to create a Backup from my phone and other computers to my Debian Server) or something like that. Not sure if this is your case, but keep in mind any variable before upgrade.

Aptik can help you to export your ppa’s, icons, themes, programs settings and much more. Perhaps you also want to export your shell history (.bash_history file) inside your /home. If you can’t find, after open Nautilus press CTRL+H in order to see the hide stuff…

If you’re a Firefox user, then you can import all the favorites from other browsers you have and then export in .JSON/HTML file or (much better!), if you have a Mozilla account, your stuff is synced automatically with other Firefox installations.
You’re a Chrome user + Gmail account? Then you can sync your favorites, passwords and other info between all your Chrome browsers. Since the default browser on Ubuntu is Firefox (Mozilla account is not limited to Gmail, but other email providers are also welcome), it can be a good idea to use Firefox to get all the data from other browsers (no matter if Opera, Edge[No April’s Fool, I promise!]) and, why not? As default browser for safe Internet use without worrying about telemetries from companies such as the Big G…

Nowadays, the email config is IMAP on most email programs and providers so, no matter you’re using Thunderbird, Eudora, The Bat… If is set to IMAP; next time you install or configure Thunderbird or any other email program, all your content will be available. Otherwise (POP3), create a Backup as soon as possible since your content is not synced with your provider. Anyway, it is not a bad idea to backup all your contacts or verify if your email and contacts is the same using the webmail that your provider offers you.

Finally, if you made a fresh install (formatting your HDD) create your /home apart from the rest of partitions; if something goes wrong next time you upgrade your system, your data will be safe and sound. For your 1TB, I recommend you to create 250GB for “/” (ext4 format), from2 to 8GB for Swap, 600GB for your /home (ext4 too, or LUKS if you want to cipher your data) and the rest (± 50GB) for Backup purposes such as TimeShift or Déjà-Dup. If you have any external drive, you could create (with the help of Ventoy) not only a boot drive to help you to instal Ubuntu 20.04, but also to create Backups using RescueZilla, Clonezilla or any other Bare Metal Backup solution…

Hope this helps you,


Thank you BennyBeat, Nina and Akito for taking the time to school me on all things involved with backups. I use Chromium web Browser and Thunderbird Email with a POP3 account. You have all given me more than enough to look into. Many things I never considered, I do use Timeshift. I was not aware that RescueZilla or Clonezilla could be used for backups. I am going to be busy this weekend learning new skills. Thanks to you all.

1 Like