NFS won't start, down the rabbit hole we are going

NFS stopped working? 

systemctl start nfs-server.service - hangs and tells you to check journalctl -xe ??

journalctl -xe saying something about a missing drive, even though the drive was never exported?

-- Subject: Unit nfs-server.service has failed

-- Defined-By: systemd

Feb 14 20:31:16 amber systemd[1]: nfs-server.service: Job nfs-server.service/st>

Feb 14 20:31:16 amber systemd[1]: seagate8.mount: Job seagate8.mount/start fail>

Feb 14 20:31:16 amber systemd[1]: dev-disk-by\x2dlabel-seagate8.device: Job dev>

Feb 14 20:31:16 amber systemd[1]: dev-disk-by\x2dlabel-seagate7.device: Job dev>

Feb 14 20:31:16 amber systemd[1]: Timed out waiting for device Expansion_Desk s>

-- Subject: Unit dev-disk-by\x2dlabel-seagate7.device has failed

WAIT! No need to reboot! Hey, this isn't Windows, we can fix it!

And the solution (likely) is: 

systemctl daemon-reexec

OR

systemctl daemon-reload

The the reason NFS won't run (in some cases) has nothing to do with NFS or /etc/exports - it's a problem with systemd. One could consider it a "feature" or a bug. Personally I think systemd is a bug, causes more trouble than it solves. I've seen and fixed this NFS won't start problem several times over the years and finally got around to writing down the solution, as from Google I see a ton of posts with these errors messages and no correct answers. Just a lot of jump through hoops, chase down rabbit holes and check your kernel module FUD.

2021 ISP speeds

     Server: Winchester Wireless - Winchester, VA (id = 21859)

        ISP: Shentel Communications

    Latency:    13.59 ms   (2.46 ms jitter)

   Download:   101.47 Mbps (data used: 86.0 MB)                               

     Upload:    10.46 Mbps (data used: 9.9 MB)                               

Packet Loss:     0.0%

 Result URL: https://www.speedtest.net/result/c/59e0b2d6-d137-4772-970b-56fda42a92e5

     Server: Shentel - Edinburg, VA (id = 3785)

        ISP: Shentel Communications

    Latency:    11.39 ms   (5.41 ms jitter)

   Download:   261.87 Mbps (data used: 424.2 MB)                               

     Upload:    10.48 Mbps (data used: 10.3 MB)                               

Packet Loss:    13.3%

 Result URL: https://www.speedtest.net/result/c/4f7dadd6-1d85-42e0-8a5e-2de736347db9

locnar<1098>% date

Fri 19 May 16:56:48 PDT 2023

2022

 Server: Lumos Fiber - Waynesboro, VA (id = 7085)

        ISP: Shentel Communications

    Latency:    16.88 ms   (3.79 ms jitter)

   Download:   159.52 Mbps (data used: 164.9 MB)                               

     Upload:    10.22 Mbps (data used: 9.7 MB)   

 

1  gateway2 (89.7.1.30)  0.200 ms  0.217 ms  0.192 ms

 2  10.228.32.1 (10.228.32.1)  11.670 ms  21.255 ms  21.303 ms

 3  10.17.0.205 (10.17.0.205)  21.666 ms  21.858 ms  21.909 ms

 4  10.25.0.109 (10.25.0.109)  23.564 ms  23.621 ms  23.598 ms

 5  204.111.0.65 (204.111.0.65)  23.034 ms  22.949 ms  30.933 ms

 6  * * *

 7  108.170.240.97 (108.170.240.97)  29.647 ms  16.025 ms 209.85.252.18 (209.85.252.18)  15.405 ms

 8  108.170.246.49 (108.170.246.49)  24.230 ms 108.170.240.112 (108.170.240.112)  23.915 ms 108.170.246.49 (108.170.246.49)  24.058 ms

 9  * * 216.239.42.137 (216.239.42.137)  24.570 ms

10  108.170.225.156 (108.170.225.156)  29.315 ms 142.251.66.21 (142.251.66.21)  28.831 ms *

11  142.250.57.144 (142.250.57.144)  29.263 ms 142.251.69.63 (142.251.69.63)  39.602 ms 142.251.49.86 (142.251.49.86)  24.270 ms

12  108.170.248.33 (108.170.248.33)  24.154 ms  24.180 ms 108.170.248.97 (108.170.248.97)  31.631 ms

13  216.239.40.167 (216.239.40.167)  22.523 ms 216.239.40.187 (216.239.40.187)  29.248 ms 216.239.40.167 (216.239.40.167)  28.411 ms

14  lga34s38-in-f4.1e100.net (142.251.40.196)  28.576 ms  29.010 ms  29.115 ms

Apple ][ relics

 

Tapwave Zodiac and other cool handheld devices

Tapwave Zodiac 2

Best app - EDGE

GeForce GT 710 graphics card and Fedora Linux

 It works. Plug and play.

Where this get interesting is after installing the Nvidia drivers, which you don't need as the Nouveau drivers that come with Linux work just fine. I had a go with Nvidia drivers and this fanless $35 card to see if there would be any difference in picture quality over the build in graphics card on my ThinkCentre M93p running Fedora 32. Doesn't seem to be any difference as far as I can tell. Except for the one film I have in x265.10bit.HDR format, playback is choppy. I noted Kodi says the GT710 does not support the x265 codex, so no hardware excelleration. However, when I switched to the Nvidia drivers, playback of my x265 4K file is smooth.

Here's where the fun started. With the Nvidia drivers installed, the card wasn't getting the same EDID info from my Athem AVM 60 media center as I did with the Nouveau drivers. When I switched to the Nvidia drivers, Pulseaudio  (pavucontrol) showed the HDMI audio profiles as unplugged unavailible, so no sound. Even with Pulseaudio disabled, Kodi would see 4 HDMI profiles, but no sound.

edid-decode /sys/class/drm/card0-HDMI-A-1/edid

EDID and xorg.conf files

 

Welcome to Linux emergency mode! Enter control-d to continue

 

If you're stuck in this "emergency mode" boot cycle, and/or the system just hangs on boot, a common reason is a mistake in /etc/fstab. Recently I removed a drive but forgot to delete the entry in fstab, and it bit me on reboot. Just boot rescue mode, mount the / file system and edit the fstab.

Scanning on Linux will drive you Xsane!

xsane is an excellent tool for scanning on Linux, I've used it for 25 years, since I worked with the developer to resolve some issues running it under Solaris long ago. Until my recent upgrade to Fedora 31, everything worked fine with Xsane, with my old Epson USB scanner and then my Brother network scanner.  All of a sudden, xsane was giving "segmentation fault, core dumped" on start up, but only on 1 of the computers running Fedora 31, my main desktop.  On the others it worked fine. Here's the problem I found:

locnar<885>% gdb xsane
(gdb) run
Starting program: /usr/bin/xsane
Thread 1 "xsane" received signal SIGSEGV, Segmentation fault.
0x00007fffee9c07c0 in sanei_scsi_close ()
   from /usr/lib64/sane/libsane-epkowa.so.1

This ibsane-epkowa.so.1 was installed by the iscan package. Once I removed it, the trouble disappeared. I reinstalled xsane and sane-backends, followed by running linux-brprinter-installer-2.2.2-1 and I was back to scanning!

One issue I ran into with linux-brprinter-installer was it tried to install .deb packages and I need the .rpm packages on Fedora. This was because it tests to see if you have /bin/dpkg, which I did along with alien, so it thought I was on the wrong OS.