Verifying SD card capacity

Day 20

I have been on a self-hosting adventure lately. I was successful in setting up Pi-hole, Gitea, Linkding and Komga to some extent on my Pi 3B but kept running into issues and app breakdowns resulting in reinstalling everything thrice in two weeks time. To cut a long story short, the original no name micro SD card died and I bought a new one from Sandisk.

After having read reports of how fake Sandisk SD cards were common, I thought of testing the card before writing anything to it. Mounted the card and checked the capacity. 30 Gig reported.

df -h /media/sajesh/3430-3462/

The next test was to ascertain the reported capacity by writing 30 Gig of data onto the card and reading the same. Installed the tool F3 to help me do that.

f3write /media/sajesh/3430-3462/

F3 filled the card without any fail with a set of 30 files. It took some time as the writing speed was just 14.31 MB/s. A higher capacity card or disk will take much longer time. Next step was to read all the files to verify whether the write was successful.

f3read /media/sajesh/3430-3462/

So far so good. So the card can write 30 Gig and read 30 Gig. It's an original card after all.

Although F3 shows the average read and write times, every helpful website kept saying dd is a more accurate way of calculating SD card speed. I did run it but see the result for yourself.

Anyway, I just have to use this card to enable USB boot in the Pi so that I can boot from an m.2 SATA SSD. More on this later.

Join Me in #100DaysToOffload