I have 2 PC Engines apu2d4 boxes in service, and both have been rock solid, with NetBSD 9 and now 10. Probably earlier NetBSD on one of them.
A 3rd was crashy/hangy, irregularly sort of week or so with 9, and more like a few days with 10. Mostly it was silent hang (there is no console connected). The 3rd had a different problem - a bad ethernet cable, moved from wm0 to wm1 and then replaced. I realized that the configuration of dhcpcd was different solid1: dhcpcd $int in ifconfig.wm0, wm1 manual (router) solid2: dhcpcd=YES, with all of wm0/wm1/wm2 brought up, but only wm0 having a cable to a switch crashy3: dhcpcd=YES, same as solid2, but wm1 not wm0. Then, I changed the configuration of crashy3 to "allowinterfaces wm1" and it has been up for 54 days. So, I suspect there is something about wm(4) where whatever dhcpcd does to it provokes a locking bug -- but that's way out on a limb. Trying to probe further, on crashy3 I ran "dhcpcd wm2" and saw that wm2 was UP but still no carrier. Survived several days. Today did "dhcpcd wm0" and wm0 did not come UP. I do not find a way to ask the running dhcpcd for status (which interfaces are you trying on, how are they), and `dhcpcd -U` does not work: #> dhcpcd -U dhcpcd_readdumptimeout yet _dhcpcd 687 0.0 0.1 19108 2284 ? S 19Mar26 1:26.10 dhcpcd: [manager] [ip4] [ip6] root 688 0.0 0.0 22840 1584 ? S 19Mar26 1:14.57 dhcpcd: [privileged proxy] _dhcpcd 692 0.0 0.0 21680 1376 ? S 19Mar26 0:05.03 dhcpcd: [network proxy] _dhcpcd 694 0.0 0.0 18820 1380 ? S 19Mar26 0:02.47 dhcpcd: [control proxy] To be clear I am not suggesting there is a bug in dhcpcd that causes the crash/hang. I am also not 100% sure that this crashy3 box is 100% hardware-healthy -- but so far this feels like software. I wonder if anyone has wisdom or related experience.
