When I originally used the InvisaGig in 5G/LTE mode, speeds were atrocious (sub 1Mbps), but a 5G phone nearby was reach 300Mbps+.
On “paper” everything looked fine. Latency was typical, although there were spikes to 8s+. Less than 3% packet loss observed. Constructing a HTTPS connection to a CDN took upwards of 6s+. All green on the modem status page, but internet status constantly warned that host names can’t be resolved (switching back to green on the next check). Oddly, I was also seeing the text messages page hang.
After a couple hours of debugging different things (I originally suspected my mobile ISP was doing some shenanigans), I tried to switch to LTE and magically speeds were acceptable (100Mbps+).
Well, this was unexpected.
Diving deeper, I found that the 5G phone was using 5G via NSA and the modem was trying SA. Disabling SA in the modem/re-enabling 5G, quickly resolved the issue, and speeds were what was expected (300Mbps+).
So I guess my question is:
Is it typical to need to disable SA? Is my area just weird? Or is there another problem that I should be fixing (e.g. that particular band is just heavily congested and I should avoid it, I need to improve reception, etc.)?
I also don’t know if InvisaGig should have figure it out automatically. My understanding is that we’ll all transition to SA at some point, so it seems hard-disabling SA could cause hidden problems in the future (hopefully the upcoming metrics endpoint will help diagnose that though!).
(I only know the L2+ side of the networking stack, the modem is a box of black magic, so humor me if this is a 101 type of question )
Aside: I noticed that when the InvisaGig was in this “unhappy” state, the TTY would constantly disconnect every few seconds (which made this all very annoying to debug). Not sure if there’s a bug there or not. (a direct SSH/telnet service would be awesome!)