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Who When What Removed Added
Red Hat Bugzilla 2022-11-04 07:15:52 UTC Pool ID sst_storage_io_rhel_9
Red Hat One Jira (issues.redhat.com) 2022-11-04 07:26:25 UTC Link ID Red Hat Issue Tracker RHELPLAN-138306
Rob Evers 2022-11-28 15:53:31 UTC Assignee revers emilne
Doc Type --- If docs needed, set a value
Ewan D. Milne 2023-01-12 20:59:02 UTC Flags needinfo?(tbskyd)
tbsky 2023-01-13 01:27:38 UTC Flags needinfo?(tbskyd)
Ewan D. Milne 2023-02-17 20:29:42 UTC Priority unspecified medium
Status NEW ASSIGNED
Target Release --- 9.3
Keywords Triaged
ChanghuiZhong 2023-02-20 00:30:25 UTC CC czhong
QA Contact storage-qe czhong
Simon Matter 2023-03-02 08:11:05 UTC CC simon.matter
Orion Poplawski 2023-03-18 01:59:24 UTC CC orion
Charles Wei 2023-06-07 01:49:44 UTC CC cwei
CKI KWF Bot 2023-07-17 17:32:06 UTC Link ID Gitlab redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/2819
CKI KWF Bot 2023-07-17 17:32:08 UTC Status ASSIGNED POST
Ewan D. Milne 2023-07-17 17:35:03 UTC Target Milestone rc beta
Ewan D. Milne 2023-07-17 17:50:04 UTC Flags needinfo?(czhong)
Ewan D. Milne 2023-07-17 17:56:56 UTC Flags needinfo?(tbskyd)
ChanghuiZhong 2023-07-18 00:39:56 UTC Flags needinfo?(czhong)
tbsky 2023-07-18 01:25:15 UTC Flags needinfo?(tbskyd)
ChanghuiZhong 2023-07-20 08:51:16 UTC CC emilne
Flags needinfo?(emilne)
Ewan D. Milne 2023-07-20 12:23:10 UTC Flags needinfo?(emilne)
CKI KWF Bot 2023-07-21 20:41:07 UTC Status POST MODIFIED
Jan Stancek 2023-07-24 12:19:43 UTC Fixed In Version kernel-5.14.0-344.el9
Ewan D. Milne 2023-07-24 16:06:27 UTC Doc Text Feature: New kernel parameter to keep disk order consistent

Reason:

Modern Linux kernels, including RHEL 9, utilize asynchronous
device probing in order to speed up boot time. This
can result in different device number assignments for SCSI
devices (sda, sdb, etc.) on successive boot iterations.

Red Hat documentation recommends the use of persistent device
names (/dev/by-id links) in order to ensure that the correct
device is used. This is particularly important for SAN-attached
devices which may not all be present at boot time.

However, the variability in device numbering can now more
commonly occur even in systems with only local disks present.

To improve consistency in SCSI disk device numbering, a new
kernel option "sd_mod.probe=sync" has been added to use
synchronous device probing instead of asynchronous device
probing for SCSI devices.

Result: With the "sd_mod.probe=sync" option, SCSI device enumeration is now performed synchronously, which reduces the
variability in device numbering on successive boot attempts.
Ewan D. Milne 2023-07-24 16:32:37 UTC Doc Text Feature: New kernel parameter to keep disk order consistent

Reason:

Modern Linux kernels, including RHEL 9, utilize asynchronous
device probing in order to speed up boot time. This
can result in different device number assignments for SCSI
devices (sda, sdb, etc.) on successive boot iterations.

Red Hat documentation recommends the use of persistent device
names (/dev/by-id links) in order to ensure that the correct
device is used. This is particularly important for SAN-attached
devices which may not all be present at boot time.

However, the variability in device numbering can now more
commonly occur even in systems with only local disks present.

To improve consistency in SCSI disk device numbering, a new
kernel option "sd_mod.probe=sync" has been added to use
synchronous device probing instead of asynchronous device
probing for SCSI devices.

Result: With the "sd_mod.probe=sync" option, SCSI device enumeration is now performed synchronously, which reduces the
variability in device numbering on successive boot attempts.
Feature: New kernel parameter to keep disk order consistent

Reason:

Modern Linux kernels, including RHEL 9, utilize asynchronous
device probing in order to speed up boot time. This
can result in different device number assignments for SCSI
devices (sda, sdb, etc.) on successive boot iterations.

Red Hat documentation recommends the use of persistent device
names (/dev/by-id links) in order to ensure that the correct
device is used. This is particularly important for SAN-attached
devices which may not all be present at boot time.

However, the variability in device numbering can now more
commonly occur even in systems with only local disks present.

To improve consistency in SCSI disk device numbering, a new
kernel option "sd_mod.probe=sync" has been added to use
synchronous device probing instead of asynchronous device
probing for SCSI devices.

Result: With the "sd_mod.probe=sync" option, SCSI device enumeration is now performed synchronously, which reduces the
variability in device numbering on successive boot attempts.

NOTE: Even with synchronous SCSI disk probing, it is still possible
for the device numbering (and sda, sdb. etc. device names) to
change on successive boot attempts. For example, a disk may
fail to respond, or a RAID controller configuration may have
changed. For this reason, Red Hat strongly continues to
recommend the use of persistent device names (/dev/by-id links).
Ewan D. Milne 2023-07-24 16:35:43 UTC Doc Text Feature: New kernel parameter to keep disk order consistent

Reason:

Modern Linux kernels, including RHEL 9, utilize asynchronous
device probing in order to speed up boot time. This
can result in different device number assignments for SCSI
devices (sda, sdb, etc.) on successive boot iterations.

Red Hat documentation recommends the use of persistent device
names (/dev/by-id links) in order to ensure that the correct
device is used. This is particularly important for SAN-attached
devices which may not all be present at boot time.

However, the variability in device numbering can now more
commonly occur even in systems with only local disks present.

To improve consistency in SCSI disk device numbering, a new
kernel option "sd_mod.probe=sync" has been added to use
synchronous device probing instead of asynchronous device
probing for SCSI devices.

Result: With the "sd_mod.probe=sync" option, SCSI device enumeration is now performed synchronously, which reduces the
variability in device numbering on successive boot attempts.

NOTE: Even with synchronous SCSI disk probing, it is still possible
for the device numbering (and sda, sdb. etc. device names) to
change on successive boot attempts. For example, a disk may
fail to respond, or a RAID controller configuration may have
changed. For this reason, Red Hat strongly continues to
recommend the use of persistent device names (/dev/by-id links).
Feature: New kernel parameter to keep disk order consistent

Reason:

Modern Linux kernels, including RHEL 9, utilize asynchronous
device probing in order to speed up boot time. This
can result in different device number assignments for SCSI
devices (sda, sdb, etc.) on successive boot iterations.

Red Hat documentation recommends the use of persistent device
names (/dev/by-id links) in order to ensure that the correct
device is used. This is particularly important for SAN-attached
devices which may not all be present at boot time.

However, the variability in device numbering can now more
commonly occur even in systems with only local disks present.

To improve consistency in SCSI disk device numbering, a new
kernel option "sd_mod.probe=sync" has been added to use
synchronous device probing instead of asynchronous device
probing for SCSI devices.

Result:

With the "sd_mod.probe=sync" option, SCSI device enumeration is now performed synchronously, which reduces the
variability in device numbering on successive boot iterations.

NOTE: Even with synchronous SCSI disk probing, it is still possible
for the device numbering (and sda, sdb. etc. device names) to
change on successive boot iterations. For example, a disk may
fail to respond, or a RAID controller configuration may have
changed. For this reason, Red Hat strongly continues to
recommend the use of persistent device names (/dev/by-id links).

This module option is primarily being provided to
assist customers migrating from earlier versions of RHEL to
RHEL 9 and may be removed in a future major release.
errata-xmlrpc 2023-07-25 00:12:42 UTC Status MODIFIED ON_QA
ChanghuiZhong 2023-07-31 03:26:51 UTC Status ON_QA VERIFIED
Jon Magrini 2023-08-03 13:10:13 UTC CC jmagrini

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