I have a 12 TB USB drive connected to the Raspberry Pi 4 running Raspbian. The drive is formatted as btrfs.

The original line for this drive on fstab is

UUID=”8afd87a4-f10e-11ea-9666-bfec6b15c3e4″ /mnt/btrfsdrive btrfs defaults 0 0

The major issue is when USB drive is offline, RPi4 would not boot. A simple google search directs me to the well-known ArchLinux wikipage. This page implies that nofail,x-systemd.device-timeout=1ms works like a charm. I tried it and find it s**ks. When the USB drive is connected, only some directories are seen after booting, and this partition is NOT even shown in /proc/mounts

The root cause is obvious after comparing the booting log in /var/log/messages. timeout=1ms is not acceptable at all. In fact, the default timeout value is 90 seconds.

Not sure whether this issue happens only on RPi 4, or Raspbian, or Linux. Anyway, suggesting user to set such a small timeout value is misleading.

I am not able to correct the mistake on that wiki because the captcha during registration is What is the output of “pacman -V|base32|head -1” and I won’t install ArchLinux to get the answer…

Log of fstab options=default

Sep 7 20:51:33 myhost kernel: [ 23.019520] Btrfs loaded, crc32c=crc32c-generic
Sep 7 20:51:33 myhost kernel: [ 23.021470] BTRFS: device label myelements devid 1 transid 74693 /dev/sda
Sep 7 20:51:33 myhost kernel: [ 23.298985] BTRFS info (device sda): disk space caching is enabled
Sep 7 20:51:33 myhost kernel: [ 23.299003] BTRFS info (device sda): has skinny extents
Sep 7 20:51:33 myhost kernel: [ 27.445768] random: crng init done
Sep 7 20:51:33 myhost kernel: [ 27.445793] random: 7 urandom warning(s) missed due to ratelimiting
Sep 7 20:51:33 myhost rsyslogd: [origin software=”rsyslogd” swVersion=”8.1901.0″ x-pid=”385″ x-info=”https://www.rsyslog.com”] start
Sep 7 20:51:33 myhost kernel: [ 39.738751] uart-pl011 fe201000.serial: no DMA platform data
Sep 7 20:51:33 myhost kernel: [ 39.763978] 8021q: 802.1Q VLAN Support v1.8
Sep 7 20:51:33 myhost udisksd[401]: udisks daemon version 2.8.1 starting

Log of fstab options=nofail,x-systemd.device-timeout=1ms

Sep 7 20:44:44 myhost kernel: [ 22.972058] Btrfs loaded, crc32c=crc32c-generic
Sep 7 20:44:44 myhost kernel: [ 22.974082] BTRFS: device label myelements devid 1 transid 74693 /dev/sda
Sep 7 20:44:45 myhost kernel: [ 23.440453] broken atomic modeset userspace detected, disabling atomic
Sep 7 20:44:45 myhost kernel: [ 24.015551] broken atomic modeset userspace detected, disabling atomic
Sep 7 20:44:46 myhost lightdm[1325]: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Accounts was not provided by any .service files
Sep 7 20:44:46 myhost kernel: [ 24.976452] broken atomic modeset userspace detected, disabling atomic
Sep 7 20:44:47 myhost kernel: [ 25.577489] broken atomic modeset userspace detected, disabling atomic
Sep 7 20:44:47 myhost lightdm[1335]: Error getting user list from org.freedesktop.Accounts: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.freedesktop.Accounts was not provided by any .service files
Sep 7 20:44:48 myhost kernel: [ 26.430257] broken atomic modeset userspace detected, disabling atomic
Sep 7 20:44:48 myhost kernel: [ 27.014250] broken atomic modeset userspace detected, disabling atomic
Sep 7 20:50:53 myhost udisksd[358]: udisks daemon version 2.8.1 exiting