Bug 2313526

Summary: udev creates /dev/sda1 symlink for Amazon Elastic Block Store NVMe
Product: [Fedora] Fedora Reporter: Vojtech Trefny <vtrefny>
Component: amazon-ec2-utilsAssignee: Major Hayden 🤠 <mhayden>
Status: CLOSED DUPLICATE QA Contact:
Severity: high Docs Contact:
Priority: unspecified    
Version: 41CC: daan.j.demeyer, fedoraproject, lnykryn, mhayden, mpitt, msekleta, prajnoha, ryncsn, suraj.ghimire7, systemd-maint, tbzatek, yuwatana, zbyszek
Target Milestone: ---Keywords: Reopened
Target Release: ---   
Hardware: Unspecified   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2024-09-23 14:50:37 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Vojtech Trefny 2024-09-19 12:31:02 UTC 
When running tests with packit using tmt which runs the tests in AWS I noticed the NVMe drive present on the system has  /dev/sda1 symlink created for the /dev/nvme0n1 device. Similarly /dev/sda11, /dev/sda12 etc. symlinks are created for partitions on the NVMe.

udev version: systemd-udev-0:256.5-1.fc41

udev properties for /dev/nvme0n1:
-----
'CURRENT_TAGS': ':systemd:', 
'DEVLINKS': '/dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0dd9d3f42ab640d3f 
    /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0dd9d3f42ab640d3f-ns-1 
    /dev/disk/by-diskseq/1 
    /dev/disk/by-id/nvme-uuid.ae346bed-d818-5ce0-b2f1-cae0e3bdfdc8 
    /dev/sda1 
    /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0dd9d3f42ab640d3f_1 
    /dev/disk/by-path/pci-0000:00:04.0-nvme-1', 
'DEVNAME': '/dev/nvme0n1', 
'DEVPATH': '/devices/pci0000:00/0000:00:04.0/nvme/nvme0/nvme0n1', 
'DEVTYPE': 'disk', 
'DISKSEQ': '1', 
'ID_MODEL': 'Amazon Elastic Block Store', 
'ID_NSID': '1', 
'ID_PART_GPT_AUTO_ROOT_UUID': 'cf4ad69d-fe1d-4c10-addd-1d3b2ed99d29', 
'ID_PART_TABLE_TYPE': 'gpt', 
'ID_PART_TABLE_UUID': '3dd46407-ccbc-436f-8400-6d6928832861', 
'ID_PATH': 'pci-0000:00:04.0-nvme-1', 
'ID_PATH_TAG': 'pci-0000_00_04_0-nvme-1', 
'ID_REVISION': '2.0', 
'ID_SERIAL': 'Amazon_Elastic_Block_Store_vol0dd9d3f42ab640d3f_1', 
'ID_SERIAL_SHORT': 'vol0dd9d3f42ab640d3f', 
'ID_WWN': 'uuid.ae346bed-d818-5ce0-b2f1-cae0e3bdfdc8', 
'MAJOR': '259', 
'MINOR': '0', 
'SUBSYSTEM': 'block', 
'TAGS': ':systemd:', 
'USEC_INITIALIZED': '3933501'
-----

udev properties for /dev/nvme0n1p1:

-----
'CURRENT_TAGS': ':systemd:', 
'DEVLINKS': 
    '/dev/disk/by-diskseq/1-part1 
    /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0cb54fb95bd126c62_1-part1 
    /dev/disk/by-partuuid/56befb49-9d1c-4863-a956-a13cebc6ce9c 
    /dev/disk/by-partlabel/p.legacy /dev/disk/by-path/pci-0000:00:04.0-nvme-1-part/by-partlabel/p.legacy 
    /dev/disk/by-path/pci-0000:00:04.0-nvme-1-part/by-partnum/1 
    /dev/sda11 
    /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0cb54fb95bd126c62-ns-1-part1 
    /dev/disk/by-id/nvme-Amazon_Elastic_Block_Store_vol0cb54fb95bd126c62-part1 
    /dev/disk/by-path/pci-0000:00:04.0-nvme-1-part1 
    /dev/disk/by-path/pci-0000:00:04.0-nvme-1-part/by-partuuid/56befb49-9d1c-4863-a956-a13cebc6ce9c 
    /dev/disk/by-id/nvme-uuid.6dd6db11-29a0-5c99-b13c-7fcd49f035fa-part1', 
'DEVNAME': '/dev/nvme0n1p1', 
'DEVPATH': '/devices/pci0000:00/0000:00:04.0/nvme/nvme0/nvme0n1/nvme0n1p1', 
'DEVTYPE': 'partition', 
'DISKSEQ': '1', 
'DM_MULTIPATH_DEVICE_PATH': '0', 
'ID_MODEL': 'Amazon Elastic Block Store', 
'ID_NSID': '1', 
'ID_PART_ENTRY_DISK': '259:0', 
'ID_PART_ENTRY_NAME': 'p.legacy', 
'ID_PART_ENTRY_NUMBER': '1', 
'ID_PART_ENTRY_OFFSET': '2048', 
'ID_PART_ENTRY_SCHEME': 'gpt', 
'ID_PART_ENTRY_SIZE': '4096', 
'ID_PART_ENTRY_TYPE': '21686148-6449-6e6f-744e-656564454649', 
'ID_PART_ENTRY_UUID': '56befb49-9d1c-4863-a956-a13cebc6ce9c', 
'ID_PART_GPT_AUTO_ROOT_UUID': 'cf4ad69d-fe1d-4c10-addd-1d3b2ed99d29', 
'ID_PART_TABLE_TYPE': 'gpt', 
'ID_PART_TABLE_UUID': '3dd46407-ccbc-436f-8400-6d6928832861', 
'ID_PATH': 'pci-0000:00:04.0-nvme-1', 
'ID_PATH_TAG': 'pci-0000_00_04_0-nvme-1', 
'ID_REVISION': '2.0', 
'ID_SERIAL': 'Amazon_Elastic_Block_Store_vol0cb54fb95bd126c62_1', 
'ID_SERIAL_SHORT': 'vol0cb54fb95bd126c62', 
'ID_WWN': 'uuid.6dd6db11-29a0-5c99-b13c-7fcd49f035fa', 
'MAJOR': '259', 
'MINOR': '1', 
'PARTN': '1', 
'PARTNAME': 'p.legacy', 
'SUBSYSTEM': 'block', 
'TAGS': ':systemd:', 
'USEC_INITIALIZED': '3994407', 
'_NS_ID': '1'
-----

Reproducible: Always
Comment 1 Lukáš Nykrýn 2024-09-23 10:43:09 UTC 
It seems that there is some Amazon mapping from nvme names to sd ones
https://docs.aws.amazon.com/ebs/latest/userguide/identify-nvme-ebs-device.html
Comment 2 Tomáš Bžatek 2024-09-23 13:41:39 UTC 
So, in case the nvme id-ctrl structure contains something vendor-specific like the encoded "sda" string, what mechanism is used to extract this field and make a symlink?
Comment 3 Lukáš Nykrýn 2024-09-23 14:17:01 UTC 
https://github.com/amazonlinux/amazon-ec2-utils/blob/main/70-ec2-nvme-devices.rules
Comment 4 Lukáš Nykrýn 2024-09-23 14:20:30 UTC 
Anyway, this seems to be related to amazon infrastructure and not related to systemd itself.
Comment 5 Tomáš Bžatek 2024-09-23 14:27:58 UTC 
Thanks Lukas! Let's reopen and reassign to amazon-ec2-utils as this really needs to be fixed.

One possible solution might be to lower priority of such symlinks so that they get properly overwritten by regular device rules. If there's no real scsi device that the name should belong to, it won't change anything to the users. If a real device appears, then the Amazon symlinks should become invalid.
Comment 6 Tomáš Bžatek 2024-09-23 14:30:34 UTC 
See udev(7) and link_priority= option, in this case negative numbers might help.
Comment 7 Tomáš Bžatek 2024-09-23 14:38:59 UTC 
Duplicate of bug 2284397

Upstream issue: https://github.com/amazonlinux/amazon-ec2-utils/issues/37
Comment 8 Zbigniew Jędrzejewski-Szmek 2024-09-23 14:50:37 UTC 

*** This bug has been marked as a duplicate of bug 2284397 ***