Mount by label or UUID of EBS volumes (NVME) not working with EC2 C5 instances

[michael8888]

I am unable to mount EBS volumes in C5 instances via UUID or label. For instance this doesn't work with Ubuntu 18.04:

e2label /dev/nvme1n1 DATA
mkdir /data
mount -L DATA /data

There is no error message, but the volume won't be mounted

However, I can mount this way:
mount /dev/nvme1n1 /data

I have the same problem when I try to mount via UUID.

This all works fine in C4 instances.

I need to mount this way because NVME volumes are randomly assigned to device names. This causes problems in fstab if you stop the instance and launch it again. I can mount mount via volume id. However, this then causes problems if you create a new AMI from the instance.

This seems to be an Ubuntu issue. I just tried it with Amazon Linux and mounting via labels works there. I also was able to mount a local SSD via label. However EBS volumes don't work.

This what I see in syslog:

Sep 21 11:50:43 ip-10-0-0-145 kernel: http:// 915.753600 EXT4-fs (nvme2n1): mounted filesystem with ordered data mode. Opts: (null)
Sep 21 11:50:43 ip-10-0-0-145 systemd[1]: Unmounted /data.
Sep 21 11:51:47 ip-10-0-0-145 systemd[1]: data.mount: Unit is bound to inactive unit dev-xvdg.device. Stopping, too.

Maybe a Ubuntu bug?