You will need a new or repurposed microSD card with a capacity of at least 32 GB -- since this is a server we might want to store lots of photos or videos on it. See the Ubuntu MATE website for some examples of microSD cards. Recently I was able to buy a 256 GB Silicon Power microSD card for less than $25 Cdn on Amazon; this brand is rated highly for use on Raspberry Pi's by testers like Tom's Hardware.
Go to
the Ubuntu MATE download website
to download your image - for a Pi 4 generation with 4 or more GB of RAM
the 64-bit ARM architecture (arm64) is best. For the version I used in
March 2023 the image name was:
ubuntu-mate-22.04-desktop-arm64+raspi.img.xz.
There are many instructions available online to help you download the disk image and install it onto installation media - I will not reproduce the instructions here. How you create the image depends on your home computing device and its OS. There is a helpful tutorial on creating the installation image using the Raspberry Pi Imager software for 3 operating systems:
After installing the disk image on the microSD the disk partitioning looks like this using the fdisk command. I show it here so that you are aware of what is going on under the hood. Here is an example of a 256 GB microSD inserted into a USB card reader on another Linux computer where the card showed up as /dev/sde:
$ sudo fdisk -l /dev/sde
Disk /dev/sde: 231.68 GiB, 248765218816 bytes, 485869568 sectors
Disk model: FCR-HS3 -3
...
Disklabel type: dos
Disk identifier: 0x11d94b9e
Device Boot Start End Sectors Size Id Type
/dev/sde1 * 2048 499711 497664 243M c W95 FAT32 (LBA)
/dev/sde2 499712 12969983 12470272 5.9G 83 LinuxThere are 2 partitions; the first (/dev/sde1) is a small boot partition whose type is FAT32, and the second (/dev/sde2) is the minimal 6 GB Linux partition. Though this microSD is 256 GB, only the first 6 GB is currently used. The automatic installation process will expand the partition right to the maximum extend of its partition or of un-allocated space. Most Linux installation images allow you to choose your disk partitioning; the Raspberry Pi Ubuntu installation image does not.
However, it is possible and useful to modify the pre-installation partitioning directly on the microSD card as described in the appendix.
In the appendix I also provide a generic Linux command-line approach to downloading, un-compressing and writing the image to the microSD card. If you are not yet very familiar with the command-line then leave this exercise for a later time in your Linux adventure.