A start job is running for dev-disk-by (…)

After a full system upgrade I got following message, which was blocking the startup for 1 min and 30 secs:

A start job is running for dev-disk-by\x2duuid-db1d2b48\x2d0cfb\x2d4bdf\x2dabe8\x2dfb287a4274d5.device

So I took a look here and there.
And investigated a little further.. (and learned a thing or two about Swap.)

Problem Analysis

Boot log

$ journalctl -b
 Apr 19 12:31:50 felipe-arch systemd[1]: Job dev-disk-by\x2duuid-db1d2b48/start timed out.
 Apr 19 12:31:50 felipe-arch systemd[1]: Timed out waiting for device dev-disk-by\x2duuid-db1d2b48\x2d0cfb\x2d4bdf\x2dabe8\x2dfb287a4274d5.device.
 Apr 19 12:31:50 felipe-arch systemd[1]: Dependency failed for /dev/disk/by-uuid/db1d2b48-0cfb-4bdf-abe8-fb287a4274d5.  
 Apr 19 12:31:50 felipe-arch systemd[1]: Dependency failed for Swap.

Aparently something with UUID and Swap is wrong.

What is swap status?

$ cat /proc/swaps 
Filename                                Type            Size    Used    Priority

There is nothing there!

Is fstab right?

$ cat /etc/fstab 
# /dev/sda3 LABEL=archlinux
UUID=cbe6287b-c136-49b6-a3d5-8cdd5b739293       /               ext4            defaults,data=ordered   0 1
# /dev/sda4
UUID=db1d2b48-0cfb-4bdf-abe8-fb287a4274d5       none            swap            defaults        0 0
/dev/sda2       /mnt/windows    ntfs-3g defaults,uid=melladric,gid=users,umask=0022     0       0

What is Swap UUID?

$ lsblk -f
 NAME   FSTYPE LABEL     UUID                                 MOUNTPOINT
 sda                                                          
   sda1 ntfs   SYSTEM    3494F2D494F29796                     
   sda2 ntfs             A06C77246C76F47E                     /mnt/windows
   sda3 swap             a7fa69a8-31bd-448c-98de-55de4aa6f06a 
   sda4 ext4   archlinux cbe6287b-c136-49b6-a3d5-8cdd5b739293 /
 sr0

Swap UUID in fstab is incorrect!