SSD
HDD will never finish IBD
Discussion
HDD can finish IBD but now we're talking a few months
Exactly
Why would it take so long?
The IOPS for a typical hard drive is about 300-500. Conversely for an SSD its 10s of thousands. Writes may be constrained to under 50000 while reads may generally be closer to 100000. Thats like a 100x difference.
These numbers will vary by individual device comparison but suffice to say the SSD is going to be substantially faster for reads and writes.
The Bitcoin IBD sync and verification will perform lots of reads and writes. On a raspberry pi 4 sync on an SSD may be about 5 days. On a hard drive, id guess 3-4 months. CPU is also a bottleneck, so if on a beefier refurbushed PC or NUC, the initial IBD and sync may be 1-2 days.
My tiny pc has a an 8th Gen i5-8600 (6 core, 35W TDP processor. I can't stand raspis. So just that alone pushes me to an SSD since it will be fast enough to not screw up. This is making enough sense now.
Why? I know several people with HDs that are running just fine.
That's OK then feel free to wait ~3-6 months for IBD
Spinning disks do not read/write fast enough compared to SSD's
My internet connection on my server will be way lower than the read/write speed of any modern drive. Does it really take that long to download the blockchain?
With HDD I've known many folks (including myself) that the IBD never completed (blocks come in faster than the HDD can validate block headers)
Internet speed doesn't matter*
Its all about how your device reads/writes data
*any basic ISP package will suffice