Start job delaying boot -- Solved

Hey Guys,
So I use Pop OS in my main rig and I am a hardware junky. I had a couple of blank disks sitting around in the PC from when I used to try out distros. I set up a new larger swap file on sda and added a couple of new mounts to make the disks usable as extra space so it looks like this.

gemma@pop-r7:~$ lsblk -f
├─sda1 swap 1 swap 59a7efef-24ba-441e-9550-ba3774492619 [SWAP]
└─sda2 ext4 1.0 20cf5b4a-fcad-4e3c-a8a8-29d29dc78fdd 775.7G 0% /home/gemma/fast
└─sdb1 ext4 1.0 4aa3dc49-1e13-44c0-a284-8cb81fb3e924 553.6G 0% /home/gemma/slow
└─sdc1 ext4 1.0 4096 7598ebb5-28c3-4b85-bff4-351b61bde114
├─nvme0n1p2 ntfs Recovery 6249D67161CEDB76
├─nvme0n1p3 vfat FAT32 F5FA-C62A
└─nvme0n1p4 ntfs Win2048 9C26F4710825595D
├─nvme1n1p1 vfat FAT32 AD43-D9AF 191.6M 61% /boot/efi
├─nvme1n1p2 vfat FAT32 AD43-DD31 1.9G 52% /recovery
└─nvme1n1p3 ext4 1.0 876b13f2-40a8-4a58-b5a4-019cd758a32e 477.6G 42% /

This is all working fine, once the boot has completed.
My issue is that during boot I get the following message

“A start job is running for /dev/disk/by-uuid/4a8f1fa-etc-etc”

This message is displayed for about a minute before giving up and completing the boot. This partition uuid is the old 4GB swap which used to be on nvme1n1 which I deleted when I made the new swap partition.

My question is how would I identify the start job which is pointing at this deleted partition such that I can point it at the new swap partition?

my fstab

# /etc/fstab: static file system information.
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
# <file system>  <mount point>  <type>  <options>  <dump>  <pass>
PARTUUID=dea34e66-7d03-4026-83f5-60e51bf3b793 /boot/efi vfat umask=0077 0 0
PARTUUID=0252a219-4fb8-4d8c-8f89-8b7104a8755c /recovery vfat umask=0077 0 0
UUID=876b13f2-40a8-4a58-b5a4-019cd758a32e / ext4 noatime,errors=remount-ro 0 0
#/dev/mapper/cryptswap none swap defaults 0 0
UUID=59a7efef-24ba-441e-9550-ba3774492619 none   swap    sw      0      
UUID=20cf5b4a-fcad-4e3c-a8a8-29d29dc78fdd /home/gemma/fast/ ext4 noatime,errors=remount-ro 0 0
UUID=4aa3dc49-1e13-44c0-a284-8cb81fb3e924 /home/gemma/slow/ ext4 noatime,errors=remount-ro 0 0

What’s the output of swapon -s ?

gemma@pop-r7:~$ swapon -s
Filename Type Size Used Priority
/dev/sda1 partition 102399996 0 -2

Try sudo dmesg or look at the file /var/log/dmesg for other clues.
I’m not sure what you should be looking for, I’ve never had to search dmesg for this issue before.

systemd is your friend
systemd-analyze blame will output a list of how long each job took
systemd-analyze plot > plot.svg will make an SVG of each job durring start. hopefully it will help you find which job is hanging

1 Like

Thanks I’ll try these later.


Using the logs I found the issue was cryptswap. I don’t know whether this is a Pop OS thing or if its in common usage but this is what happened.

I identified a file called /etc/crypttab in there was an fstab looking line with the old UUID. I replaced this with the new UUID. Next in /etc/fstab I removed the entry I had made for the regular swap and reenabled the cryptswap line commented above. Then I rebooted and… it booted quickly.

Thanks for the tip on the logs. As a software dev (for windows) I use logs all the time but knowing where to look is half the battle.