Just to advise that this has worked as i planned and effectively mirrored a 1gb SD card to a 64GB SD card through the IDSDM module. All systems up and running. Thanks.
Size "Size can be difficult to estimate with SD cards; just because two cards are the same size (1GB) does not mean they contain the same number of available blocks. During a mirror rebuild, the size of the secondary card must have an equal or greater number of bytes available than the primary card. The easiest way to validate this is to select the card from within an OS, and request the size of the disk."
I attempted this same scenario (Replaced one 1GB card with a 32GB card, let it re-mirror, then replaced the other card), and while that worked, the system insists the cards are just 1GB cards. Even booting into gparted still shows the raid as 1GB, still. Even breaking the mirror didn't show the new larger size of the two cards.
Perhaps the IDSDM works differently in an R815 than in your system?
@Fazaman This likely has to do with the partition table being copied block for block during the mirror process, a 1GB partition written to a 32GB SD Card is still a 1GB 'volume' in the eyes of the operating system. To fix this you would need to 'expand' the partition with a utility such as GParted, or possibly even Windows DiskPart.
@DavidHelpTech As I said, I used gparted, for exactly the reason you said. I had suspected, as you do, there would be free space after the 1gb partion, but it was displayed as a 1gb drive. Not a 1gb partition on a 32gb drive that I could expand into. The controller, (IIRC from my research at the time) only worked with 1gb cards, and didn't support anything larger. So, regardless of the size you put in there >1gb, you'd only ever see 1gb.
I ended up using the hard drives that came with the system that we had initially removed when we built the system years earlier.
Russem
1 Rookie
•
6 Posts
0
March 15th, 2023 07:00
Just to advise that this has worked as i planned and effectively mirrored a 1gb SD card to a 64GB SD card through the IDSDM module. All systems up and running. Thanks.
DELL-Young E
Moderator
•
5.4K Posts
0
November 1st, 2022 19:00
Hi, thanks for choosing Dell.
Size
"Size can be difficult to estimate with SD cards; just because two cards are the same size (1GB) does
not mean they contain the same number of available blocks. During a mirror rebuild, the size of the
secondary card must have an equal or greater number of bytes available than the primary card. The
easiest way to validate this is to select the card from within an OS, and request the size of the disk."
https://dell.to/3UjNHhM page 6
Hope this helps.
Fazaman
1 Rookie
•
2 Posts
0
April 17th, 2023 11:00
I attempted this same scenario (Replaced one 1GB card with a 32GB card, let it re-mirror, then replaced the other card), and while that worked, the system insists the cards are just 1GB cards. Even booting into gparted still shows the raid as 1GB, still. Even breaking the mirror didn't show the new larger size of the two cards.
Perhaps the IDSDM works differently in an R815 than in your system?
DavidHelpTech
1 Rookie
•
1 Message
0
January 9th, 2026 21:37
@Fazaman This likely has to do with the partition table being copied block for block during the mirror process, a 1GB partition written to a 32GB SD Card is still a 1GB 'volume' in the eyes of the operating system. To fix this you would need to 'expand' the partition with a utility such as GParted, or possibly even Windows DiskPart.
Fazaman
1 Rookie
•
2 Posts
0
January 9th, 2026 22:48
@DavidHelpTech As I said, I used gparted, for exactly the reason you said. I had suspected, as you do, there would be free space after the 1gb partion, but it was displayed as a 1gb drive. Not a 1gb partition on a 32gb drive that I could expand into. The controller, (IIRC from my research at the time) only worked with 1gb cards, and didn't support anything larger. So, regardless of the size you put in there >1gb, you'd only ever see 1gb.
I ended up using the hard drives that came with the system that we had initially removed when we built the system years earlier.